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General Category => General Discussion => Topic started by: Vasco DG on November 17, 2014, 03:54:21 AM
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Interestingly I'm finally beginning to see cam failures coming through in my shop. Things that are worth noting.
1.) The failures are all occurring in spring after a wet winter.
2.) They usually manifest themselves immediately after a service. I have no certain idea why. The only thing I can think of is that the high carbon content of the dirty oil may contribute some form of added protection and once new, clean oil is in circulation it all goes pear shaped very quickly.
3.) Engines seem to start misbehaving long before there is visible damage to the tappets but at the same time similar wear patterns on functioning cams do not seem to necessarily be terminal. For example I inspect my cams and tappets about every six to nine months and while they have a similar 'Pattern' on their nose circles, (Which is where the cam failures begin oddly, rather than the opening flank as I'd expect.) but my great lump of Munt soldiers on seemingly impregnably!?!
4.) Long before the valves become really noisy signs of the demise of the cams and tappets will begin to manifest themselves by firstly misfiring and hesitation as the throttle is opened with no load at about 2,000-2,500 rpm, this is easy to overlook if you don't know what you're listening for. Secondly the engine will start spitting back through the throttle bodies, this can be both seen and heard, at idle. A drop of engine speed and a 'Chuff' accompanied by the physical rearward movement of the TB's between the boot to the manifold and trumpet to airbox.
To paraphrase our ridiculous governments propaganda about chanting fanatics be alert but not alarmed. Keep your oil hot and ride 'em hard. They'll be far less likely to fail if you thrash 'em!
Pete
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Thanks Pete.
I'm doing my best to flog her. It's easy to do!
Kurt
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Well it starts before you hear it, in the picture look at the dlc that is not even anymore, and that gave the heating on the cam lobe. That makes the cam rough, and that then takes the rest of the tappet away. It can take 2mm of the tappet. But anyway the engine runs and brings you home.
(http://s28.postimg.org/fn1fvayf1/DSC03738_Medium.jpg)
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Pete,what brand oil are you putting in those bikes? Average miles on the bikes? Brand specific cam failures in cars after thousands of miles are mostly bad heat treating on cam and or what makes contact with the cam . Oil with low ZDDP can be a factor but years ago when some OHV and OHC auto engines had epidemic failures it was bad materials..
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So many questions!
How many of these have you seen?
Can any of the failures be attributed to poor break-in, lack of proper maintenance, or abuse? Or is it happening despite the owner doing everything "by the book?"
Is there any pattern as far as model, year, or date of manufacture?
Are these engines still under warranty?
For bikes either within or outside of the warranty period, what has been the factory's response as far as parts, repairs, and financial responsibility?
What does fixing this entail, and what is the cost? Are the failed engines getting upgraded to roller tappets?
Have any of the failures occurred among the engines with roller tappets? If not, from the damage that you have inspected, do you anticipate that the roller engines will not have these failures?
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Oil with low ZDDP can be a factor but years ago when some OHV and OHC auto engines had epidemic failures it was bad materials..
Ditto on both points.
A little inexpensive insurance-
http://barsproducts.com/catalog/view/245-3x-concentrated-engine-oil-supplement-with-zinc-treatment-4405
http://zddplus.com/
Considering the past issue with materials hardness (and the recall) that afflicted early Stelvio models, I'm wondering if a smattering of that same issue from the same suppliers may be a persisting issue.
The overall incidence of failures may be small, though. I dunno.
.
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we had all abuse and oil discussions in the past, not doing it over again. In German Stelvio forum we made a list of members with the problem. 30 until now.
http://www.razyboard.com/system/morethread-liste-aller-betroffenen-mit-nockenwellenschaden-stelvioforum-1988046-6198716-310.html
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I just surpassed the 50,000 mile mark on my Stelvio and have noticed a few symptoms.
The backfire through the throttle bodies happens but only on startup after a spirited ride.
Valve lash has been an issue this summer with frequent adjustment. Exhaust valves on left bank in particular loosing up. I even had a couple of valve tighten up a bit on this last check. Never had any real issue in this regard for at least the first 30,000. I did notice a faint but unusual noise in the engine and GuzziSteve replaced the two exhaust lifters on the left side due to unusual wear patterns. The cam looked ok at that time. Everything seems ok except that it always seems to come back to the same suspects.
Fortunately, the engine has always run as it should and I do ride it as Pete recommends but I may well do the roller tappet upgrade before the worse happens.
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As Paul says this has been discussed ad-nauseam there is no need to cover the same ground again. I am certain I know the cause and the recent nature of the failures I'm seeing is relevant hence my mentioning it as a new data point. I'm only now, seven years into the life of the engine, beginning to see failures in my shop.
With the bikes I'm seeing I'm catching the damage early and so far on these bikes there is, at least to me with my bad hearing, no audible signature to the failure, it's the poor running that has alerted me and a check of the valve lash has confirmed it. Once the hard coating has gone from the tappets though they wear quickly and THEN they get real noisy, real quick.
Pete
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Sounds faintly similar to Lario issues, though the cause is not necessarily similar. I DLC coated my cam/tappets in hopes of better wear. Is this something anyone considers Pete? Makes perfect sense, but pricey yeah.
Kevin
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In the 80s Mercedes had a rash of cam failures. It seemed to be across the board, 6&8 cylinder gas motors as well as 4&5 cylinder diesels. All over head cam engines. The theory was, the oil would be forced out from between the cam and follower while stationary. On start up, the hardness would gradually be scraped away. Once the hardness was gone, the cam would wear quickly.
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Sounds faintly similar to Lario issues, though the cause is not necessarily similar. I DLC coated my cam/tappets in hopes of better wear. Is this something anyone considers Pete? Makes perfect sense, but pricey yeah.
Kevin
Stock tappets are DLC.
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First 8V cam failure in Norway?
Never heard of one until it happened to me a month ago...
Started it up to take it to the shop for winterizing in October, two days after oil and filter change at 48K kilometers on the meter, and heard a more pronounced valve ticking sound.
Last oil change before this was in the authorized Guzzi repair shop at 41K. The bike has been serviced by skilled mechanich at an authorized Guzzi garage every 10K kilometers since new.
And I have changed motor oil and filter between the ordinary service intervall.
About the valve sound: Didn't give it much thought other than I thought it probably had to do with cold start in chilly weather.
Didn't notice anything unusual on my way to the garage. Didn't notice anything unusual on my daily Stelvio trips the days before either.
A few days later the mechanic contacted me and told me that the valve clearance was more out of specs than it had been before.
A closes inspection revealed this (very visible cam lobe wear and "curved" wear on the tappets) :
(http://s25.postimg.org/z0zi4ue27/slitt_kam.jpg)
(http://s25.postimg.org/kj2awumr3/slitt_kam_2.jpg)
The bike is a 2012 modell 8V, registered on me as the first owner in september 2012, engine no. AC012543, build March 14th according to the mechanic at the local Guzzi garage.
He contacted the importer promptly after the miserable discovery and confirmed the day after that the whole package will be covered by the warranty – new parts and the repair:
I have to admit that I've become a bit skeptic to the Moto Guzzi quality after this. I seriously think that such wear shouldn't be happening on a well-built bike like this after just 48 K kilometers.
Fortunately things seems to turn out good for me and I hope that the flat tappet design will be replaced with roller tappets and make my Stelvio fit for fight again when Spring is here in a few months:
(http://s25.postimg.org/hh2lmolrj/Stelvio_7800.jpg)
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Stock tappets are DLC.
Doesn't make sense that one is and one isn't. You're only as good as your weakest link. Of course it's only now that we're finding out the weak link or contributing theories on cause.
Kevin
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It should also be remembered that there have been two or maybe three updates to the flat tappets. The original A5 motors used chilled cast iron tappets which there was a recall on. All of these should of been replaced by the forged steel with DLC type used in the A8 and on motors. At some later point, I think around 2012 sometime from memory the part number for the forged tappets changed but they still appear identical to the earlier ones so it might just of been due to a change of supplier.
Some, especially in cool, damp climates fail very quickly. Some, like mine, seem to soldier on forever. Certainly understanding the 8V and servicing it correctly makes a big difference. Using mineral oil in it is a recipe for disaster but is alas very common. I remain skeptical about the whole ZDDP issue but ensuring the oil has a higher level certainly can't do any harm. Understanding the extremes of heat and cooling seems to be most important factor in longevity and prevention in my experience.
Pete
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Pete,
You mentioned in a recent thread that in cold weather one should restrict the air flow to the oil cooler on an 8V. How do you determine how much to restrict without either over or under doing it?
GliderJohn
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Do a search for the 'Simply Brilliant' thread.
I use an oil temperature dipstick to ascertain oil temperaure. Having an adjustable baffle gives flexibility. Anyone with half a brain will soon be able to look at the ambient temperature on the dash and quickly work out how much baffling is needed to keep the oil temperature up with a bit of experience. The temp guage can then be used to confirm it.
Pete
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Thanks Pete.
GliderJohn
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I recently rode to Swamp Scooters in Louisiana...a 2500 mile round trip. On most days I was riding in the 50s to 60s but there were a couple mornings where I started out in the low 40s. I found that I could always rest my bare hand on the valve cover, even at 75mph on the Interstate . That tells me that the oil was only getting up to about 150F at most. On part of the return trip I put two strips of Duct tape across the bottom of the oil cooler. That did not change anything. Next I'll add another two layers and check with an IR thermometer. The NTX has such a huge oil radiator it's going to take significant blockage to get the oil up to 220-250F, where I would like to see it. My gas mileage was only 36 mpg and I attribute that to over cooling.
Peter Y.
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Pretty quickly after taking ownership of my Stelvio I put on this cover. At the time I wondered if I was restricting the cooling too much. I'm not concerned after reading this thread. Above 85F I can feel the heat coming off the cylinders on my legs. I've ridden in 95F-102F for hours at 80mph+ on the Stelvio (2012) with no issues.
(http://i393.photobucket.com/albums/pp19/demar39/mg182.jpg)
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Interestingly I'm finally beginning to see cam failures coming through in my shop. Things that are worth noting.
4.) Long before the valves become really noisy signs of the demise of the cams and tappets will begin to manifest themselves by firstly misfiring and hesitation as the throttle is opened with no load at about 2,000-2,500 rpm, this is easy to overlook if you don't know what you're listening for. Secondly the engine will start spitting back through the throttle bodies, this can be both seen and heard, at idle. A drop of engine speed and a 'Chuff' accompanied by the physical rearward movement of the TB's between the boot to the manifold and trumpet to airbox.
Pete
I know you've dismissed this before but #4 is classic inlet valve recession, if you ever get one at this stage (spitting back) check clearances then, my bet is tight not loose. Then at zero clearance it goes pear shaped VFQ.
Trying to help, not criticise . Are the ones you're seeing now all four lobes ?
Are you seeing any tight clearances ever ?
Pic of valve head after tits up cam should show story too
MH
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Clearances aren't the issue, believe me.
Pete
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If oil operating temperature is a concern, a thermostat can be added to any oil cooler not so equipped.
http://wildguzzi.com/forum/index.php?topic=73346.msg1143225#msg1143225
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The issue with that is that it is weighty, complex and adds a whole heap of leak points. It also wouldn't be cheap and would be an eyesore. If you don't mind those things then yes, it's an alternative. My own favourite is Mark Salkeld's sollution which is cheap, simple and will work just as well but required a bit of owner input.
Pete
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Those thermostats are not very large and can be nestled in to the cooler circuit pretty discreetly. I have one that is barely 2 inches square and plan to install on my Stelvio. I'll post pics later.
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Ya know, the more I read here about this topic, the more I wonder if this is not a quality control issue with metals, hardness etc as has occurred in the past.
Many thousands of cam-in-head BMW 1100, 1150 and 1200 boxer engines built from 1994 to 2010 had a "flat tappet" type valve lifter design. BMW has experienced issues in other areas but I have not yet heard about serious premature wear issues related to these flat lifters.
Part #5, BMW parts fiche
(http://i1213.photobucket.com/albums/cc462/leafman60/Miscellaneous/BMWlifter.png) (http://s1213.photobucket.com/user/leafman60/media/Miscellaneous/BMWlifter.png.html)
Even the 2010-2013 and the new 2013-2014 water cooled engines with overhead cams do not use any roller device but utilize a flat "drag lever" that rides on the camshaft.
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Clearances aren't the issue, believe me.
Pete
What makes them spit back, falter at idle etc ? As you say this is the big clue, loose clearance won't envoke this, somehow there is spark happening in manifold, on old engines this can only be ignition timing or valve leak, on modern MX bikes it is always valve problem, search CRF Honda valves, million theories why, but changing not adjusting the only way, once they've started they keep recessing.
After service is another clue, if valves were tight, then clearance reset, sounds like deja vu all over again, I met this issue a long time ago.
Hope I'm wrong but it's so very familiar.
MH
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Well it will if you understand the fueling parameters. Martin, I'm sure you have extensive experience in failures of this type on other, probably carbureted, machines. The symptoms will be markedly different on a machine that fuels mainly from sensor input rather than atmospheric pressure. And yes, I do know there is an air pressure sensor.
Pete
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I did some research on DLC as I was considering it for the Daytona engine I'm rebuilding. Apparently it's ok on tool steel lifters but nothing else and I think its an issue if you float a valve. fails badly if that happens from memory due to the impact.
With what Pete outlined and others feedback on the pre cursers to lifter issues, would instead of valve seat recession being the cause of running issues it may be an intermittently sticking valve?
That would give the same symptoms as the riding valve and also pound the lifters badly whan the clearances opened up which may cause lifter failures.
Would also be more likely with machines that are little used in a cold climate.
Just something to consider from left field.
Ciao
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I don't understand why I am getting "we have discussed this before" in response to my specific questions about these specific incidents that you have been experiencing of late, Pete, but I have been following this issue with great interest, and I believe these are important questions that have not been previously answered. (How could they? They pertain to incidents that you first disclosed in this thread one day ago.) Of course, it is your prerogative to ignore them, but I really wish you wouldn't.
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Pete, you have stated your theory that this problem is caused primarily in cold, wet climates and results from moisture condensing on the inside of the valve covers and finding its way down to the lifter mechanism causing microscopic rust that results in premature wear.
If this is true, how about lining the inside of the valve cover with an insulating barrier of gasket cork or maybe felt to inhibit such condensation. I'm not totally buying into this theory but, if it is correct, an insulation barrier on the inside of the cover or even just positioned across the valve mechanism without contact should help.
About 30 years ago, on a cold winter morning, I had ridden my Shovelhead a short distance afterwhich I decided to check the primary chain tension. When I removed the slick chrome derby cover to expose the inside of the primary chaincase, the inside of the derby cover was coated with moisture-emulsified oil that looked like mayonnaise.
Moisture had condensed on the inside of the chrome steel derby cover and mixed with the oil. With about 10-15 minutes of continued riding, this was all burned off and the oil looked clear. I went ahead and adhered a layer of gasket cork to the inside of that derby cover that is still there after 30 years. It totally stopped that source of condensation and any mayonnaise that I get must be bought from the store (but I don't use it).
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Am I courting disaster by running my 09 griso 8v in cold weather? Is it advisable to let it warm up at idle? Should I periodically pull the cam boxes to inspect for wear or is close monitoring of valve lash adjustment adequate to catch this early? Love this bike, but wont have a bike I cant ride because its cold or damp. Enough questions for now , thanks Dave. ps I realize there is probably no simple answer to these questions.
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I don't understand why I am getting "we have discussed this before" in response to my specific questions about these specific incidents that you have been experiencing of late, Pete, but I have been following this issue with great interest, and I believe these are important questions that have not been previously answered. (How could they? They pertain to incidents that you first disclosed in this thread one day ago.) Of course, it is your prerogative to ignore them, but I really wish you wouldn't.
Sorry, but the reason I say it's been discussed before is because it has, almost endlessly, in a multitude of threads. Those who are interested will either of seen these ramblings or, if they wish, can do a search here or on any one of a number of boards and get the skinny on how and why I developed my theory as to why the damage occurs and why geographical location is relevant.
It is neither necessary or useful for me to completely re-state every step I have undertaken to analyse and rule out different causes for the failures, hence my comment to Martin that it isn't a clearance option, that was something I ruled out very early in the piece as it was an obvious cause, and yes, I've had the heads off both failed and healthy cammed bikes and there are no signs of valve recession. I've checked most if not all of the *obvious* causes for failure and although I'm only now beginning to get failures through my shop, (As noted after a very cool, damp winter.) I have seen the guts of multiple failed bikes and have had enough experience tearing down 8V engines to know that the manual often lies, (Look at the thermostat in the cooling system issue.) and what happens in various parts of the engine in various temperatures and conditions.
As I've said before I may be quite wrong in my diagnosis but it is at least a diagnosis based on scientific observation, documentation and repeatable results. I've also pestered people world wide for specific information regarding failures on their or their customers bikes. It's been a long, slow haul.
Pete
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Am I courting disaster by running my 09 griso 8v in cold weather?
Probably, if you only use it for short trips and don't get it hot enough.
Is it advisable to let it warm up at idle?
No, idling won't warm the oil up in any significant way, the engine has to work to make heat.
Should I periodically pull the cam boxes to inspect for wear or is close monitoring of valve lash adjustment adequate to catch this early?
No point in pulling the camboxes all the time. As soon as wear begins the gaps will open up appreciably, normally 8V's need only tiny adjustments at the 10,000Km service interval. If the gaps open by more than a thou you've probably got a problem. Note also that while it isn't a check that allows 100% certainty observing the tops of the tappets where they poke through the top of the cambox casting is another useful check. When the cam and tappets are healthy with the piston at TDC compression as when you are checking valve lash the tappets are usually ever so slightly proud of the top of the cambox casting, (15-30 thou say.). Once the tappets start to wear the tops will drop to flush or below flush with the top of the cambox. This is clearly visible, even to my old eyes!
Love this bike, but wont have a bike I cant ride because its cold or damp. Enough questions for now , thanks Dave. ps I realize there is probably no simple answer to these questions.
If you have a FSH and your flat tappets fail then the factory will give you a roller conversion, if the bike is outside of its warranty period you have to pay for installation. If your bike is festooned with aftermarket junk like O2 sensor foolers or Power Commanders, has no name filters and Wally-world oil in it? Forget it!
Pete
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The above photo of the tappets with the DLC missing in the centers interests me. Since DLC is a non-wearing very thin coating I'd think the tappets would be ground absolutely flat and would run on a cam lobe that was also flat (rather than the conventional very slight crowned tappet and tapered cam lobe). No matching "break-in" wear would occur with DLC coatings. SO...my question is: Are the DLC coated tappets and matching cams ground flat or has Guzzi coated tapered parts and caused localized overloading of the tappet resulting in lost DLC in the centers? Once that coating chips it'll be like a lathe cutting the cam lobe down.
Might be I'm all wet here but that's what crept into my feeble mind this afternoon as I attempt to thaw from this hellish cold spell!
Terry
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I'd considered that and my mind is still open as to it being a contributory factor but it is the timing and geographical nature of the failures that points me away from it as a primary cause.
Pete
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Lucian, when running logging runs for map testing in cold weather, I found it takes a very long time (even at 60 mph) to get the 8V up to a 'hot' state of 96C (204F) when you are cruising on the open road. Up to 20 minutes. Now if you are riding slower through town or in a stop/start situation, it may never get hot enough to vaporize water. That's without rain. Water splashing onto the sump exacerbates the situation. The only way to get it not enough was too thrash it. That is high revs at low gear, for a long time. Even then, once returning to cruise, the temp would plummet.
It's my opinion that those who commute in town or stop/start riding all year long through cold weather and rain are in the greatest danger of failure via mayo.
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Peter
The failures you have had coming through your workshop, have they been just the older style cast iron tappets or have you been getting the later model forged steel ones as well
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Like I said in a previous thread, i think this is a big issue for Piaggio.
& Well done for documenting what you have found so far
http://wildguzzi.com/forum/index.php?topic=70319.msg1106375#msg1106375
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There was a 'Technical update', (The recall you have when you aren't having a recall.) on the original cast iron tappets which were only fitted to early A5 motors. By now there should, theoretically, be none left in service.
There certainly was an issue with these, I took some failed ones to the Australian Mint back in '09 or so and had them hardness tested on a Beakers machine and they were found to be wanting but having said that the ones in my bike never failed in 22,000km. I know that the bike before mine suffered an early failure, as did the bike after mine but I put this down mainly to poor prep and negligent servicing, (At this time a lot of shops were still working on the "It's a Guzzi, you can run any old oil in them!" Philosophy and didn't understand the nature of the oil cooling circuit.) I was absolutely anal about stuff like valve clearances during break in and yes, they do close up appreciably when new but even running the original A5 settings of 4 and 6 thou the tappets never rode the cam when hot, yes, I checked, on multiple bikes.
Pete
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Thank you Vasco and Beetle for providing concise useful answers to my questions. I know damn well I couldn't have paid my dealer to do the same. You have given myself and others, a concrete plan in place to deal with these issues in an intelligent manor. I am also gratefull for your permission to flog my griso like a red headed stepchild. Dave
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The above photo of the tappets with the DLC missing in the centers interests me. Since DLC is a non-wearing very thin coating I'd think the tappets would be ground absolutely flat and would run on a cam lobe that was also flat (rather than the conventional very slight crowned tappet and tapered cam lobe). No matching "break-in" wear would occur with DLC coatings. SO...my question is: Are the DLC coated tappets and matching cams ground flat or has Guzzi coated tapered parts and caused localized overloading of the tappet resulting in lost DLC in the centers? Once that coating chips it'll be like a lathe cutting the cam lobe down.
Might be I'm all wet here but that's what crept into my feeble mind this afternoon as I attempt to thaw from this hellish cold spell!
Terry
The reason for the slight dome on the lifter face along with the lifter bore being slightly off centre with the cam lobe centre line and a slight taper on the cam lobe is to cause the lifter to rotate and present a fresh surface to the cam and promote oil renewal between the surfaces.
There are 2 ways a lifter fails, one is due to oil film loss and the subsequent micro welding pulling the hardening off the face and the other is fatigue.
All of that loading and unloading of the coated or hardened face eventually causes fatigue below the surface and the surface breaks away. Hence the need to still have the lifters rotate to distribute the fatigue evenly.
The same applies to roller bearings, even properly lubricated and protected a roller bearing still has a "life" due to fatigue issues.
Ciao
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I was absolutely anal about stuff like valve clearances during break in and yes, they do close up appreciably
Pete
This, AFAIK there is only one place to lose valve clearance, find it and you have problem solved. If not the valve recessing, where is the clearance going ?
Are all your new failures covered in mayo ? If so, just after a service suggests some neglect, no-one would put cambox lid back on without cleaning it, surely ?
Old joke but can't stop myself
"Knock, knock"
Who's there ?
Griso
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Initially the seats will settle in the heads, there is also stuff like assembly lube that will was out allowing clearances to change, freshly cut seats bed as the valves settle into the margins. Almost all valves will close their gaps in the first few hundred Km/hours of use, some more than others. I would of thought you'd of known that?
Pete
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Initially the seats will settle in the heads, there is also stuff like assembly lube that will was out allowing clearances to change, freshly cut seats bed as the valves settle into the margins. Almost all valves will close their gaps in the first few hundred Km/hours of use, some more than others. I would of thought you'd of known that?
Pete
Once marginally is not the issue here, appreciably thereafter might be, can you get to service records of bikes that were just done before they did the trick ?
2.) They usually manifest themselves immediately after a service. I have no certain idea why. The only thing I can think of is that the high carbon content of the dirty oil may contribute some form of added protection and once new, clean oil is in circulation it all goes pear shaped very quickly.
This new information tells a good story and theory of old oil contaminants being better for DLC is dubious to say the least, can't see not changing oil as the definitive answer.
Generally speaking this is frowned upon
Long bow
When oil is changed it's possible to get air lock in cam feed oil galleries. This can happen on pushrod BB's , starving rockers for a while, normally they self bleed but I have had one that needed bleeding at crankcase.
If this is reason and they self bleed eventually, rollers rocker may be factory's easiest solution, as they possibly withstand dry for the time it takes to bleed gallery.
Are failures always on one side ? (L or R),
Hope Piaggio is covering them all
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This, AFAIK there is only one place to lose valve clearance, find it and you have problem solved. If not the valve recessing, where is the clearance going ?
Valve stretch? That's where the small blocks normally lose clearance.
Just a thought. :BEER:
Rod
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Considered that too. Yes, I have a variety of half way decent measuring sticks :D
Pete
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Sorry, but the reason I say it's been discussed before is because it has, almost endlessly, in a multitude of threads. Those who are interested will either of seen these ramblings or, if they wish, can do a search here or on any one of a number of boards and get the skinny on how and why I developed my theory as to why the damage occurs and why geographical location is relevant.
It is neither necessary or useful for me to completely re-state every step I have undertaken to analyse and rule out different causes for the failures....
So, the "it" that has been "discussed before" is the "causes for the failures?" Not to be rude, but that's not what I asked. Perhaps you didn't actually read any of my questions? Only one of them (the second one) touched on the issue of what might be causing the failures, and even that was only in a tangential way. My other questions had nothing to do with that issue.
I value your insight and experience, so I would really appreciate your consideration of the questions that I actually posed. As your stated reason for not doing so appears to be a misunderstanding of what I am asking, I will ask one more time. If there is some other reason why you don't want to answer, well... again, your prerogative to tell me to "bugger off."
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The reason for the slight dome on the lifter face along with the lifter bore being slightly off centre with the cam lobe centre line and a slight taper on the cam lobe is to cause the lifter to rotate and present a fresh surface to the cam and promote oil renewal between the surfaces.
There are 2 ways a lifter fails, one is due to oil film loss and the subsequent micro welding pulling the hardening off the face and the other is fatigue.
All of that loading and unloading of the coated or hardened face eventually causes fatigue below the surface and the surface breaks away. Hence the need to still have the lifters rotate to distribute the fatigue evenly.
The same applies to roller bearings, even properly lubricated and protected a roller bearing still has a "life" due to fatigue issues.
Ciao
This is true, and I understand it. However, I work daily with a number of diesel engines from a variety of manufacturers and those using tappets with hard coatings or inserts (like the 500 series JD diesel with Carbide disc inserts in the tappets) have no crown and no taper. Only the offset from center to promote rotation. My thoughts are based on these facts as the physics involved seem to fit the pattern of failures seen in some 8V Guzzis.
Terry
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One of my early thoughts was non-rotation of the tappets but if that was the case I would of expected different wear patterns. With your far greater experience of failures of this type I'd be interested in your opinions. I'll drag out a selection of tappets tomorrow and take some pics.
Non rotation wouldn't explain the geographic and climatic pattern to the failures though.
Pete
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One of my early thoughts was non-rotation of the tappets but if that was the case I would of expected different wear patterns. With your far greater experience of failures of this type I'd be interested in your opinions. I'll drag out a selection of tappets tomorrow and take some pics.
Non rotation wouldn't explain the geographic and climatic pattern to the failures though.
Pete
I don't know that I have far greater experience with this type failure,Pete...but I do have occasion to observe how different types of valve train treatments and machining techniques operate and survive. This stuff piques my interest and I appreciate your taking time to post photos of the offending parts. If we don't figure anything out we can always say Bugger It and go drink!
Terry
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If there is some other reason why you don't want to answer, well... again, your prerogative to tell me to "bugger off."
No, why should I tell you to bugger off? I'm not going to spoon feed you either. All of those questions have been covered extensively over the last few years. If you are really interested you will find the information and subject matter you desire.
Pete (Who forgot to take pics of failed tappets today because he was up to is neck in ot. Sorry.)
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This is true, and I understand it. However, I work daily with a number of diesel engines from a variety of manufacturers and those using tappets with hard coatings or inserts (like the 500 series JD diesel with Carbide disc inserts in the tappets) have no crown and no taper. Only the offset from center to promote rotation. My thoughts are based on these facts as the physics involved seem to fit the pattern of failures seen in some 8V Guzzis.
Terry
I see your point but you know not everything translates exactly. I'll make an assumption that the diesel engines you refer to are a direct injection type of large capacity that probably rev to 2700 rpm or there abouts, might be wrong but if so it doesn't necessarily follow that an engine with a much wider operating rpm range that can spin to 8000 rpm can get away with the same design of lifters and cam lobes
Ciao
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Keep the info coming Pete. I love my NTX and have had two years of great riding. Armed with the information you and others are providing I can monitor my flat tappets and cam condition and possibly catch an insipient failure before major damage IF it ever comes to that. Piaggio has already stated that the roller kit will be provided free of charge to anyone who has this issue even if the bike is out of warranty. I am confident I can do the install myself. I am sure as heck not going to sell the bike for a loss and go out and spend thousands more on some other brand to replace it just in case the problem MIGHT happen. Or spend the cash out of pocket for the kit and replace it just in case. If I can get 40 or 50k miles out of the current set up I have already paid for good enough. At least I will have gotten that much out of it before investing any more to keep on the road. During the mean time I will have had time to see how the new roller set up works out or who knows maybe there will be a new design change down the road that's better. No matter for me, the bike is paid for and I may as well roll with what ever comes to keep riding it. ;-T
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No, why should I tell you to bugger off? I'm not going to spoon feed you either. All of those questions have been covered extensively over the last few years....
Oh, brother! How could my questions have been answered "extensively over the last few years" when I am specifically asking about the failures THAT YOU HAVE PERSONALLY WITNESSED COMING THROUGH YOUR SHOP -- failures that you first reported here on November 17, 2014 (three days ago)?
Moreover, the question that has been "covered extensively" is the source of these failures. I DIDN'T ASK THAT QUESTION.
I am not asking to be "spoon-fed." If you know anything about how I operate, I am perfectly capable of looking up available information. However, you state that you are finally dealing personally with 8V failures in your shop, and that this is a recent phenomenon. For questions such as whether the failed 8V bikes that are in your shop now or you have recently seen are in or out of warranty, and whether Piaggio is covering all or part of the expense of repairs (and what that repair and expense entails), who else but you should I ask, and how else except by asking you now could I find the answers?
So, to be clear, FOR THE 8V FAILURES THAT YOU FIRST REPORTED HERE THREE DAYS AGO (and ONLY in regard to those bikes):
How many of these have you seen?
Can any of the failures be attributed to poor break-in, lack of proper maintenance, or abuse? Or is it happening despite the owner doing everything "by the book?"
Is there any pattern as far as model, year, or date of manufacture?
Are these engines still under warranty?
For bikes either within or outside of the warranty period, what has been the factory's response as far as parts, repairs, and financial responsibility?
What does fixing this entail, and what is the cost? Are the failed engines getting upgraded to roller tappets?
Have any of the failures occurred among the engines with roller tappets? If not, from the damage that you have inspected, do you anticipate that the roller engines will not have these failures?
FWIW, I am not asking out of idle curiosity, but to inform future purchasing decisions.
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So, to be clear, FOR THE 8V FAILURES THAT YOU FIRST REPORTED HERE THREE DAYS AGO (and ONLY in regard to those bikes):
How many of these have you seen?
Can any of the failures be attributed to poor break-in, lack of proper maintenance, or abuse? Or is it happening despite the owner doing everything "by the book?"
Is there any pattern as far as model, year, or date of manufacture?
Are these engines still under warranty?
For bikes either within or outside of the warranty period, what has been the factory's response as far as parts, repairs, and financial responsibility?
What does fixing this entail, and what is the cost? Are the failed engines getting upgraded to roller tappets?
Have any of the failures occurred among the engines with roller tappets? If not, from the damage that you have inspected, do you anticipate that the roller engines will not have these failures?
FWIW, I am not asking out of idle curiosity, but to inform future purchasing decisions.
;-T
I'm also very interested in answers to these questions.
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How many of these have you seen?
Can any of the failures be attributed to poor break-in, lack of proper maintenance, or abuse? Or is it happening despite the owner doing everything "by the book?"
Is there any pattern as far as model, year, or date of manufacture?
Are these engines still under warranty?
For bikes either within or outside of the warranty period, what has been the factory's response as far as parts, repairs, and financial responsibility?
What does fixing this entail, and what is the cost? Are the failed engines getting upgraded to roller tappets?
Have any of the failures occurred among the engines with roller tappets? If not, from the damage that you have inspected, do you anticipate that the roller engines will not have these failures?
FWIW, I am not asking out of idle curiosity, but to inform future purchasing decisions.
OK, I'll waste a bit more time for you.
1.) Several.
2.) No idea, I wasn't riding them.
3.) No.
4.) No.
5.) This has been explained a dozen times.
6.) Replacement of the camboxes with roller assemblies. Depending on motor the heads may need to come off to shim the inlet valve springs.
7.) AFAIK there have been no systemic failures of roller top ends but there again they haven't been around that long.
I strongly advise you don't buy one. You'd never enjoy it because you would always be anticipating some sort of failure. Where's the fun in that.
OK. Questions answered. Happy?
Pete
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This is fun!
If nothing else, Pete, at least everyone now realises that flat tappets are not just a pushrod thing.
Hey, what are the cam bearings, roller or plain? Any damage there? I have some relevant experience with cam failures like this that started with bearings getting smushed at cold-start due to high pressures on certain bearings. The bearing damage blocked the oil feed, which restricted flow to the cam lobe. Engines with fewer cold starts lasted many miles longer than engines in short commuting service. I have pictures...
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Cam bearings are plain, fed from high pressure circuit, no damage, always plenty of oil in evidence.
Pete
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Pete, I'm curios if any of the failed 8v's you are encountering will be upgraded to roller tappets, if so can we hope for a tutorial? Also are you seeing this both in a5 and a8 motors? Dave
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Good info, Pete!
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Thank you for answering my questions, Pete. I'm still not clear if for the 8V bikes you are repairing, Piaggio is going to pay for the repairs, but I guess I should just shut up and be grateful for the morsels of information you begrudgingly supplied, eh?
FWIW, I am still relatively happy with my EV, despite the failed clutch that left me stranded in Nowheresville, KY, and the now non-functioning speedometer / odometer / trip meter.
Hey, I might even buy a third Moto Guzzi some day (maybe even an 8V model). I guess I am just the type of person who likes to go into a major purchase with his eyes open. Weird, right?
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OK, one more time.
IF THE TAPPETS FAIL IN THE WARRANTY PERIOD AS LONG AS YOU HAVE A FULL SERVICE HISTORY THE REPLACEMENT WILL BE DONE FREE OF CHARGE AT NO COST TO THE CUSTOMER BUT PAY YOUR SHOP SHIT SO TAKE THEM IN A CASE OF BEER.
IF THEY FAIL OUTSIDE OF WARRANTY AS LONG AS YOU HAVE A FULL SERVICE HISTORY THE FACTORY THE FACTORY WILL, AT THEIR DISCRETION, SUPPLY A ROLLER CONVERSION KIT BUT THE CUSTOMER HAS TO PAY FOR INSTALLATION.
Are as clear now. No service history and you can whistle.
Pete
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If you do your own oil changes, does notes in a log book count as "service history?"
[Ducking and running....]
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Are you a qualified motorcycle mechanic? Do you own the factory approved tooling to service the machine? Have you undertaken any form of training and familiarisation with the product? Are you aware of its individual eccentricities? Finally, have you ever given anything to either your manufacturer or your dealer apart from the innital purchase price of the bike?
If the answer to one, any or all of the above is 'No' I would suggest that everybody above you in the food chain will cordially and happily instruct you to bite your bum!
Pete
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Pete, I'm curios if any of the failed 8v's you are encountering will be upgraded to roller tappets, if so can we hope for a tutorial? Also are you seeing this both in a5 and a8 motors? Dave
A5, A8, AA, AC, the full banana. No series is exempt.
See my reply in red below as to what happens in terms of replacement.
Pete (Who has just spooned on a new set of Michelin PR4's onto his flat tappet Griso and plans to go out tomorrow and see how much he can peel off the edges tomorrow on the way to the coast.) :D
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I have a kit that will fix these issues.
See:
http://www.ebay.com/itm/Moto-Guzzi-Griso-cams-lifters-DLC-coated-/321440011098?pt=Motorcycles_Parts_Accessories&vxp=mtr&hash=item4ad751535a
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Umm, no, sorry Ed, you don't. This is identical to the fix the factory tried and it hasn't worked.
Pete
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Umm, no, sorry Ed, you don't. This is identical to the fix the factory tried and it hasn't worked.
Pete
Is it fixable in your opinion ?
Wonder if anyone will ever test one, 100K miles on pushrod engine so common no-one doubts it, 50 (80 french ones) on an 8V considered high, realistic life expectancy in this day and age ?
Landfill
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Really?
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I guess I should have been clearer and more focused with my last question.
If you have a dealer do the set-up and break-in service, and you do your own oil changes and valve clearance checks/adjustments ,and keep a log, and assuming no other service is needed, will that satisfy the need for a "service history?"
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I guess I should have been clearer and more focused with my last question.
If you have a dealer do the set-up and break-in service, and you do your own oil changes and valve clearance checks/adjustments ,and keep a log, and assuming no other service is needed, will that satisfy the need for a "service history?"
Interesting question. In NY state, the owner can perform the basic maintenance and the warranty will remain in force. Any problems occurring after the warranty period, if repaired free of charge, or at some reduced rate would be due to the "good will" of the dealer/mfg. I think. This probably varies from state to state and certainly from country to country.
Peter
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^^^ Right. Magnuson-Moss Warranty Act means manufacturers cannot tie dealer service with honoring their warranty. (That does not mean that some don't try to disavow coverage over some flimsy excuse, like no proof of regular oil changes if you do them yourself.)
But, what about out-of-warranty repairs for failed 8V bikes, where Piaggio is apparently offering a so-called "hidden warranty" (at least, a partial one covering the parts, only)? If they will only supply free parts for bikes with a "service history," are they using that as a dodge, or will people who do their own oil changes and valve adjustments get treated fairly?
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To be fair - Is this a question Pete should be answering?
He can tell you what happens in his shop.
He can tell you what his experiences are.
But he can't be EXPECTED to know what's going to happen to anyone else in any other part of the world.
Eric
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To be fair - Is this a question Pete should be answering?
He can tell you what happens in his shop.
He can tell you what his experiences are.
But he can't be EXPECTED to know what's going to happen to anyone else in any other part of the world.
Eric
Yep :+1 YCRN , there is no way Pete can do anything but a SWAG here :D
Dusty
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Here's a article which could be helpful. No "cast in stone" solutions, biggest thing is to not be an *&%$hole when you ask for a gift.
Peter
http://www.dealerbusinessjournal.com/articleview.php?id=545-12072
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Again, all of my questions to Pete were specifically addressed to his personal experience with 8V failures. He may be a stubborn cuss, but he knows his shyte and I value his expertise and experience.
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Maybe Guzzi should call the dentist (John Wittner) to fix these teething problems. :D ;D
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Again, all of my questions to Pete were specifically addressed to his personal experience with 8V failures. He may be a stubborn cuss, but he knows his shyte and I value his expertise and experience.
And I can't work out whether you are a troll or just incredibly dim. I have answered your questions as best I can but you still want me to keep repeating stuff, seemingly for your entertainment! Sorry, no more.
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Interesting question. In NY state, the owner can perform the basic maintenance and the warranty will remain in force. Any problems occurring after the warranty period, if repaired free of charge, or at some reduced rate would be due to the "good will" of the dealer/mfg. I think. This probably varies from state to state and certainly from country to country.
Peter
How many 'Home Mechanics' possess Navigator or PADS? While most of us know that you can use a number of aftermarket tools to perform tasks like re-setting the TPS and the adjustable parameters of the ECU the simple fact is the only FACTORY APPROVED way of doing this is with the factory tooling. Don't have access to it? Fine! See you in court! I'm not saying this is necessarily right or fair but I'd say that legally you'd have a hard time pressing your claim. If you can't re-set your TPS you can't correctly balance your throttle bodies. If you don't keep your throttle bodies balanced you are not properly maintaining your bike. QED. Warranty declined. There is more to 'Servicing' a bike than changing its oil and adjusting the valve lash.
Pete
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How many 'Home Mechanics' possess Navigator or PADS? While most of us know that you can use a number of aftermarket tools to perform tasks like re-setting the TPS and the adjustable parameters of the ECU the simple fact is the only FACTORY APPROVED way of doing this is with the factory tooling. Don't have access to it? Fine! See you in court! I'm not saying this is necessarily right or fair but I'd say that legally you'd have a hard time pressing your claim. If you can't re-set your TPS you can't correctly balance your throttle bodies. If you don't keep your throttle bodies balanced you are not properly maintaining your bike. QED. Warranty declined. There is more to 'Servicing' a bike than changing its oil and adjusting the valve lash.
In the US, you usually don't have to visit the dealer to maintain warranty. Basically, you are free to shop around for the PROPER service. (you may need to prove that it is proper though) Or the dealer can provide it for free, if you MUST visit the dealer.
Outside of warranty, you are 100% on your own. Any dealer or manufacturing support is at their discretion.
I had a Honda that ate the cams and followers just out of warranty, they told me to take a hike. My 2004 EV never had cam issues, but out of warranty they installed an upgrade for free. I had a 7 year old Kawasaki, and they replaced the electronic ignition module for free after I wrote them a nice letter asking for their assistance. That saved me about $300.
Out of warranty depends on the phase of the moon, and how you approach the manufacturer.
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A5, A8, AA, AC, the full banana. No series is exempt.
See my reply in red below as to what happens in terms of replacement.
Pete (Who has just spooned on a new set of Michelin PR4's onto his flat tappet Griso and plans to go out tomorrow and see how much he can peel off the edges tomorrow on the way to the coast.) :D
One question not answered, and likely only Piaggio would know, is what percentage of total 8V sold have had these problems? They could even break it down by region so if it's a weather related matter this data might reveal it. Statistics done scientifically can be very revealing, but it probably for Piaggio's eyes only.
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Thanks again Pete for responding. After re-reading this thread in its entirety, I apologize for asking questions that you have clearly addressed repeatedly. I can understand your frustration. I totally understand what its like to have people who expect you to go above and beyond when the shit hits the fan,but never even throw you a bone when times are good. Happens to me all the time in my trade. I appreciate your insight as to why this happens and for your suggestions on how to proceed. I've never owned a bike that I enjoy riding as much as this griso , my cali 14 included. If it goes south on me tomorrow I will absolutely do what needs to be done to get it back on the road asap. Meanwhile I will continue to do the little stuff I can do like oil and filter, valve lash, and let a pro do the rest. Dave
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Dave, one of the reasons I post my findings and experiences up here is because it enables me to bounce ideas off and get feedback from both others in the trade and talented 'Back Yardies' that may help nail down the exact cause of the problem. I know too that others are interested in finding out why the problem is occurring. What annoys me is being constantly asked to repeat answers and re-state information that has been covered before, often multiple times. I also know that if I try to re-word what I'm saying, to make it easier to understand or to try and clarify a point, some clown will immediately jump up and start shrieking "That isn't what you said before!" Its at that point the needle on my 'I-don't-give-a-screaming-shit-o-meter' begins to swing around the dial!
As for questions as to how the problem is being addressed? I have said what I know to be the modus operandi here in Oz. I do not have a crystal ball that allows me to see into the dark souls of Piaggio management so I have absolutely no idea how it is addressed elsewhere, although the tech bulletin on our 'Australian' website is lifted directly from the Pommy one as the payment and pricing figures are all in GB£ so one assumes it is covered in the same way in that market. Extrapolating from there you would expect everywhere in the EU to get the same deal.
I personally know of one friend who has had a roller top end supplied for his Stelvio in the US so there has to be some sort of similar policy in your country. Beyond that I'm as much in the dark as anybody else. Bottom line is though if you want your dealer to help you? Help your dealer. Buy stuff off him and get your bike serviced by him/her. You can't expect people to crawl seven miles over broken glass for you for nothing.
Pete
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In the US, you usually don't have to visit the dealer to maintain warranty. Basically, you are free to shop around for the PROPER service. (you may need to prove that it is proper though) Or the dealer can provide it for free, if you MUST visit the dealer.
Outside of warranty, you are 100% on your own. Any dealer or manufacturing support is at their discretion.
I had a Honda that ate the cams and followers just out of warranty, they told me to take a hike. My 2004 EV never had cam issues, but out of warranty they installed an upgrade for free. I had a 7 year old Kawasaki, and they replaced the electronic ignition module for free after I wrote them a nice letter asking for their assistance. That saved me about $300.
Out of warranty depends on the phase of the moon, and how you approach the manufacturer.
Same worldwide IME, ditto with Honda but Yam and Suzuki bent over backwards to resolve known issues , no questions at all.
But one of things some manufacturers use to get out of warranty engine claims is the great "fiddled with" clause, non std exhausts or the very best, home tuned ECU's
If it turned out that all the 8v's that went pop had maps from the internet, could even be the genuine reason.
Any of the new "just serviced" cam failures had been "tuned" at same time with pipe and map ?.
May not be slightly relevant but Piaggio would be well within rights to knock back claim, if done by dealer it's up to him to keep shtum, as Pete says , if you want help with warranty, buy original parts from official dealer & keep receipts.
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What annoys me is being constantly asked to repeat answers and re-state information that has been covered before, often multiple times.
Pete, I think some of this comes from our "instant information" world. Some don't read the *whole* thread, or *just skim over it.* I've seen some of my "pearls of information" on small block threads do the same. Everything was addressed on the previous page, for instance. (http://i29.photobucket.com/albums/c294/elwood59/icon_shrug_zpsef3f1d1a.gif) (http://s29.photobucket.com/user/elwood59/media/icon_shrug_zpsef3f1d1a.gif.html)
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Almost certainly. Trying to be helpful and informative also seems to make you into a troll magnet which is a PITA. ::)
Pete
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OK a few pics of failed tappets and cams.
Tappets show progression of failure patterns. By the time you get to the stage the last two are at you will find junk through the motor and it needs more than a simple cam replacement!
(https://farm8.staticflickr.com/7468/15863677185_fb6e93dfef_z.jpg) (https://www.flickr.com/photos/44512000@N00/15863677185/)
The cams are interesting. Note that damage first occurs on the nose circles. It is only when the tappets get to the final point of dissolution that you begin to se developing da,age on the opening flanks.
(https://farm9.staticflickr.com/8607/15677666549_f1ba4eee2b_z.jpg) (https://www.flickr.com/photos/44512000@N00/15677666549/)
(https://farm8.staticflickr.com/7512/15863043852_0d61fa6779_z.jpg) (https://www.flickr.com/photos/44512000@N00/15863043852/)
Pete
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Interesting pics. Would the initial wear at max cam opening not point towards valve adjustment that is too tight?
Kurt
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Thanks for sharing the pics, Pete ;-T
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Tappets show progression of failure patterns. By the time you get to the stage the last two are at you will find junk through the motor and it needs more than a simple cam replacement!
(https://farm8.staticflickr.com/7468/15863677185_fb6e93dfef_z.jpg) (https://www.flickr.com/photos/44512000@N00/15863677185/)
The cams are interesting. Note that damage first occurs on the nose circles. It is only when the tappets get to the final point of dissolution that you begin to se developing da,age on the opening flanks.
Pete
Hard for me to see tappet rotation being the issue due to the circular nature of the wear.
If I was truly curious I'd take a tappet and get the hardness tested but I'd have hoped Piaggio would have done that by now.
Oil film strength may be another factor. You've mentioned the emulsified oil due to condensation before. If so and if you are getting cream up here then the breather system isn't doing its job either.
Are the valve springs progressive? If so then if the valves are too tight or any angle off 90 deg of the rocker arms to stems/lobes will add extra pressure.
Just throwing in a few abstract thoughts.
Rod
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This may be unrelated, but I recall about 15 years ago rotax was having problems with their 912 aero engines when running leaded fuels and full synthetic oils. It seems the full synthetic oils were poor at suspending lead particles and condensation debris and it was leading to severe wearout problems in their reduction gear boxes. The fix was to run a semi synthetic or dino type oil that met the engines specs and reducing the use of leaded fuels to only occasionally or not at all. The similarity that occurred to me was the "failure to suspend". Which would lead me to suspect the synthetic oils may still be lacking in some areas.
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Interesting pics. Would the initial wear at max cam opening not point towards valve adjustment that is too tight?
Kurt
No, think about it. If the gaps are too tight the tappets will ride the base circle, the nose circle is always load bearing as that is when the valve is at maximum lift. If the gaps are too tight and the tappet rides the cam there is no point in the cam's rotation where oil can get betwixt lobe and tappet so a boundary lubrication situation will occur but the point of maximum load on the cam will be on the opening flank just off the ramp where the tappet is really staring to load up and accelerate.
You can see on the cam lobes that were running the absolutely cactus concave tappets that the opening flanks had started to erode. On the 'Early Stage' failure the most obvious damage is evident on the nose circles alone.
Pete
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Thanks Pete. Excellent points.
You've really thought this through thoroughly and methodically.
Kurt
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Don't the tappets rotate /spin as they are moved up and down by the cam lobes?
And spinning under pressure and with insufficent lubrication would cause that pattern would it not?
I am guessing that moist cool air flowing over the cams during warm up might mist up the metal lobes and displace a bit of the lubricant on the tappet surfaces causing metal contact? Cool running engines can get a layer of "mayo" on the insides from the water inside not boiling out.
Especially bikes in cool moist climates with short commutes could have a moisture buildup problem inside the motor.
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Thanks Pete. Excellent points.
You've really thought this through thoroughly and methodically.
Kurt
Kurt, I'm a mechanic. It's my job. Being a 'Parts Replacer' is not being a tradesman.
Pete
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Pete,
Many thanks for the pics. If you find the time a tutorial on how us Flat Tappers should go about doing an at home cam/tappet check would be of great help. At least that way one could monitor the situation and not have to run the risk of letting things go too far. A roller conversion is bad enough with out contaminating the motor with swarf. As for your previous information on what to look for in the day to day operation of the bike I have a question. When one can see and hear the idle "Chuff/Spit Back" through the TB's how far has the damage advanced? Its obvious from your observations that one does not want to wait for excessive valve train noise to be an indicator. The no load 2 to 2.5k rpm misfire tip can be caused by any number of other ignition issues and I am afraid that one could drive a guy nuts worrying about possible cam issues. All of your effort in helping deal with this is hugely appreciated. ;-T
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Doing a chech at home, at least a preliminary one, is very easy. Just pull the rocker covers and check the valve lash. Correct clearances were originally 0.1 mm inlet and 0.15 mm exhaust on the A5 motors but this was changed to 0.15mm inlet and 0.2mm exhaust on later engines although there were no changes that would have any bearing on this in the engine itself. If it is known that the clearances were set correctly then they shouldn't change by much more than a thou or so in between services. If you check them and find that they have opened up appreciably then alarm bells should start ringing and it's time to investigate further. I would suggest that at that point it's time to get the bike to your dealer as if you start disassembling stuff further you are going to make it very hard to press a claim for replacement if you as a 'Non Approved Technician' start digging in further. If you choose to though the next step is removing the cambox and rocker gear which is pretty easy and if you wish I can describe the procedure.
Also there is no need to be excessively 'Grateful' to me for sharing the info. A problem shared is a problem halved after all. I just don't like being taken for granted, having my intelligence insulted or simply seeing the simple rules of social etiquette ignored, thassall.
Pete
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From the pics it appears Guzzi still persist with lubricating the cam lobes via the splash and hope methodology like the Daytona engine, pls correct me if i'm wrong.
What I do know is as my Daytona engine goes back together with new cams, rockers and lifters it will also have 1mm lubricating holes located just before the opening ramp on all the lobes.
Why you wouldnt put the oil directly where its needed is beyond me. I could wear it if these engines had bullit proof lifters but they dont.
Not saying its going to be the answer but it sure as hell will be an improvement.
Ciao
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There is such an abundance of oil up there I don't think that in itself is an issue. As noted it is the nose circles that seem most prone to wear rather than the opening flanks.
Pete
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There is such an abundance of oil up there I don't think that in itself is an issue. As noted it is the nose circles that seem most prone to wear rather than the opening flanks.
Pete
Any chance this is being caused by a slight woogity between the cam bearings ? Maybe an issue with the castings the bearings are riding in ?
Dusty
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Doing a chech at home, at least a preliminary one, is very easy. Just pull the rocker covers and check the valve lash. Correct clearances were originally 0.1 mm inlet and 0.15 mm exhaust on the A5 motors but this was changed to 0.15mm inlet and 0.2mm exhaust on later engines although there were no changes that would have any bearing on this in the engine itself. If it is known that the clearances were set correctly then they shouldn't change by much more than a thou or so in between services. If you check them and find that they have opened up appreciably then alarm bells should start ringing and it's time to investigate further. I would suggest that at that point it's time to get the bike to your dealer as if you start disassembling stuff further you are going to make it very hard to press a claim for replacement if you as a 'Non Approved Technician' start digging in further. If you choose to though the next step is removing the cambox and rocker gear which is pretty easy and if you wish I can describe the procedure.
Also there is no need to be excessively 'Grateful' to me for sharing the info. A problem shared is a problem halved after all. I just don't like being taken for granted, having my intelligence insulted or simply seeing the simple rules of social etiquette ignored, thassall.
Pete
Got it. My bike is out of warranty but your caution on having a dealer do the cam box and rocker gear removal is taken. I would still be interested in at least having a description of the process just in case I do decide to take a look on my own.
Thanks
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From the pics it appears Guzzi still persist with lubricating the cam lobes via the splash and hope methodology like the Daytona engine, pls correct me if i'm wrong.
I may be wrong, but I thought the cam retaining cap acts like a bucket covering the cam lobe. So the cam is constantly dipping into that oil that collects in it.
At least I thought it might be designed that way.
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Any chance this is being caused by a slight woogity between the cam bearings ? Maybe an issue with the castings the bearings are riding in ?
Dusty
Understood Pete, my thoughts were that as the cam rotates and comes off the base circle and onto the opening ramp a lubrication hole right there may just provide a wedge of oil to carry onto the nose of the cam.Cant hurt.
Ciao
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I may be wrong, but I thought the cam retaining cap acts like a bucket covering the cam lobe. So the cam is constantly dipping into that oil that collects in it.
At least I thought it might be designed that way.
Yup, I can do some pics over the next few days if people want.
Look, I'm not ruling anything in or out as to the ultimate cause but heat, climate and usage are definitely contributing factors. Just look at the history.
Pete.
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Lots of good info and hard work in this thread, thanks Pete.
Looking at the photos to me looks like a lubrication failure so your suspicion that there is a water buildup in the oil may have legs.
A couple of questions,
Have you found any mayo around these bits when you have adjusted valve clearences or pulled them out?
Any oil samples taken from the bikes with failures and sent off for analysis?
Any cams and tappets been sent off for a metalurgical inspection?
Both of which I know cost a bit of money but they may rule out shoddy manufacture or oil issues.
Are all the failure bikes using the same oil brand?
Back in the first post you stated;
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"They usually manifest themselves immediately after a service. I have no certain idea why. The only thing I can think of is that the high carbon content of the dirty oil may contribute some form of added protection and once new, clean oil is in circulation it all goes pear shaped very quickly."
Mate I've never seen carbon in oil lubricte anything, my experience is on pratt and whitney r2000 radials, masters of carbon and sludge production and an antiquated lemans is pretty much the opposite, plus I dont feel a modern fuel injected engine would produce enough carbon to do what your finding IF the oil has been changed at anywhere near the factory interval.
I do feel the the factory has either stuffed up with the specs on the surface prep on both the cams and tappets or have stuffed up the oil specification or a combination of both.
Keep the photos and reports comming, its an "interesting" problem, at least from this end with my arse on the sofa with a beer in hand.
Cheers Pete
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Pete, I also think it's a shit theory! Unfortunately it's about as logical as anything else I can think of! :D
If you look at the history though the first failures occurred, or at least we're noted publicly, in Spain and Greece, (At least according to my records.) the problem then manifested itself far more forcefully in both the UK and the Low Countries and it was at this point that it started to become evident to me that there was a climatic factor.
Early in the saga it became evident that the problem was far more prevalent in areas where there was a lot of rain, a lot of congestion and cooler winters or at least periods of the year.
I did get early tappets harness tested and they did seem to be soft. But if that was the sole cause why did my old shitter soldier on for so long when lots of others were going TU? It certainly doesn't explain why the later tappets fail or why, apart from climate, it is so random.
Examples? Mark S. Who posts as Mark III had an A5 motored G12 virtually identical to mine. It too never shat its tappets before I did the first upgrade, (That was a saga! An embarassing one! ;D) and shortly before its untimely demise he flogged it mercilessly across the entire 'Wide Brown Land' at sometimes high speeds and in harsh conditions. Like my A5, although not as bad, (Nothing is as bad as mine!) it was a raucous, noisy horror! But it never went wrong. I know of other early models that similarly soldier on seemingly impervious.
Then there are the ones that 'Fail Early, Fail Often!'.
I'd love to have a definitive answer and explanation as I love the 8V and hate the fact it still seems to have this Sword of Damaclese hovering above it! I am sure it is at least in part heat related and do NOT believe that it is a QC issue per-se. Beyond that I continue to amass data and examine the physical evidence available to me. I don't claim to have all the answers but at least I'm looking for them and to me that is better than just wailing and crying into my beer or condemning the whole engine/marque because of something that isn't fully understood.
As I've said before, I'd happily get on my horrible old Munter and ride to Perth tomorrow. If it hasn't broken by now it probably won't in my lifetime. Yes there obviously is an issue and the factory could of been more pro-active in dealing with it but I'm not going to slash my wrists over it. I'll take the Guzzi 8V over the motor in the 1200 Cappo any day. The Cappo is a bland, characterless turd. I'll put up with a bit of grief to avoid riding a turd! Fact is though I haven't had to. In 80,000 km my bike has been as reliable as an anvil!
Pete
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I did get early tappets harness tested and they did seem to be soft. But if that was the sole cause why did my old shitter soldier on for so long when lots of others were going TU? It certainly doesn't explain why the later tappets fail or why, apart from climate, it is so random.
Examples? Mark S. Who posts as Mark III had an A5 motored G12 virtually identical to mine. It too never shat its tappets before I did the first upgrade, (That was a saga! An embarassing one! ;D) and shortly before its untimely demise he flogged it mercilessly across the entire 'Wide Brown Land' at sometimes high speeds and in harsh conditions. Like my A5, although not as bad, (Nothing is as bad as mine!) it was a raucous, noisy horror! But it never went wrong. I know of other early models that similarly soldier on seemingly impervious.
Then there are the ones that 'Fail Early, Fail Often!'.
Pete
Your tappets haven't failed, nor Marks. Have you ever had either of the good tappets tested for hardness for comparison to failed tappets? Until you test a batch of them, you really can't rule out quality issues, IMO. From what I've read hear regarding the Hydro engine, it turned out to be a spring issue causing the failures. I don't know if that has stood the time test, though? Could it be the same issue with the 8v ? Maybe some springs are shimmed too tight and are coil binding, or maybe a lighter spring is needed? It seems Guzzi has been dealing with this for a while now. They need to put it to rest. That, or it's just a forum problem. ;D
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Maybe some springs are shimmed too tight and are coil binding, or maybe a lighter spring is needed?
That is my though too.
If you have a bad one, it will reappear on that same lobe because of the excess spring force.
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Disturbing finding yesterday on my A5 griso. Removed the rocker covers to find both, half covered in yellow smooze. Interestingly they were only coated on the forward half of the cover, as if the vent at the rear seems only to work on the rear half of the compartment. I should mention that the charcoal canister had been removed by the p.o. and the tubing leading to it remains dangling underneath the bike. After a spirited romp I noticed some of the dreaded mayo dripping out of the larger hose to the non existing canister which looks like it must route to the blow by tank . Anyway I cleaned off the covers, checked valve clearances, which are still in spec .10and.15, and changed the oil and filter which looked like new. I wonder if the vent system is functioning normally without the canister plumbing intact? Could this be contributing to the mayo production? I am also concerned about the tubing to the blow by and the tank itself being full off this crap. I can see in the ends of the tubes that they are lined with the emulsified oil and therefore have a reduced I.D. Wouldn't this diminish the effectiveness of the vent system? I am also wondering if the mayo only being on the forward half of the rockers could be attributed to the fact that they may be cooler in front from oncoming airflow. Are you seeing more deterioration of the tappets on the exhaust side verses intake? And should I consider removing my fuel tank and cleaning out the blow by system? This is really pissing me off!
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From the pics it appears Guzzi still persist with lubricating the cam lobes via the splash and hope methodology like the Daytona engine, pls correct me if i'm wrong.
What I do know is as my Daytona engine goes back together with new cams, rockers and lifters it will also have 1mm lubricating holes located just before the opening ramp on all the lobes.
Why you wouldnt put the oil directly where its needed is beyond me. I could wear it if these engines had bullit proof lifters but they dont.
Not saying its going to be the answer but it sure as hell will be an improvement.
Ciao
IIRC, Megacycle did that with the Lario cams, but it didn't help.
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I am also wondering if the mayo only being on the forward half of the rockers could be attributed to the fact that they may be cooler in front from oncoming airflow. Are you seeing more deterioration of the tappets on the exhaust side verses intake?
That's an interesting finding.. what about it, Pete?
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Pete,
I no longer have my beautiful pearl white 2009 Griso 8v, or any Moto Guzzi for that matter. I continue to see what's happening on wildguzzi because I know that some day I'll very likely have another Moto Guzzi. I know I'm not alone in wanting to thank you for your many years of dedication to the Moto Guzzi brand, to helping countless people improve their motorcycles and for your tireless investigation into the 8v cam failures. Plus for the many pther things you do for the Moto Guzzi community.
Thank you sir, you're a good man. I greatly enjoy reading your posts and learning from what you do and share with us.
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Removed the rocker covers to find both, half covered in yellow smooze. Interestingly they were only coated on the forward half of the cover, as if the vent at the rear seems only to work on the rear half of the compartment.
The front half of the valve cover is going to run cooler because it is in the wind. Plus, the rear half is mostly covered by the black plastic decorative cover.
It doesn't matter how well the vent system is working if the cover is too cool to cook off the moisture. We need a hat for the valve cover. ~;
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We need a hat for the valve cover.
Maybe something along the lines of what Bill Blake came up with 40some years ago.
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Pic of 1/2 shmoozed valve cover, is this typical? I can't help but think that the rear location of the vent is only servicing the rear half of the space within the cover.
https://dl.dropboxusercontent.com/u/46509859/griso/IMG_0133.JPG
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Thanks for the pics and info Pete. Much appreciated!
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Pic of 1/2 shmoozed valve cover, is this typical? I can't help but think that the rear location of the vent is only servicing the rear half of the space within the cover.
https://dl.dropboxusercontent.com/u/46509859/griso/IMG_0133.JPG
I can see there are going to be some lights on in the Guzzi garages tonight! That can't be good and seems to speak to what Pete has been saying is the problem. Aargh!
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Pic of 1/2 shmoozed valve cover, is this typical?https://dl.dropboxusercontent.com/u/46509859/griso/IMG_0133.JPG
Yes. And my 2 valve EV it is the entire cover gooed up, since the back half of it is not insulated.
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I can see there are going to be some lights on in the Guzzi garages tonight! That can't be good and seems to speak to what Pete has been saying is the problem. Aargh!
If people start pulling their rocker covers willy-nilly we'll probably have a rash of torn plug boots to contend with as well. Be careful.
The 8V's rocker covers run cooler due to the thick neoprene gaskets which are an excellent insulator. The reason why this moisture is a lot less of a problem with the old 2VPC motor is that the camshaft sits in the valley. On the 8V they sit in the camboxes in the heads where the warm, damp air will rise to when the engin is off and cooling and the Mayo that forms can drip into the weirs where the cam lobes sit through large, conveniently placed, openings in the sides of them. Is this the problem? I think so but nobody knows for sure.
The exhaust tappets fail first but this is unsurprising given their much more hostile work environment.
The springs never reach anywhere close to coilbind. In fact later models have the inlet valves shimmed for increased preload. Note that the beehive springs are rising rate and each valve uses only a single spring.
Pete
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Data point, I found the "mayo" gunk in the valve cover of my 2V 1200 Sport. During winter. I ride all year, all temps, sans Ice.
Did not see it on the Stelvio (rollers), but because the bike would be my primary transportation all year, and riding only 17 miles of highway in sub-freezing conditions are a requirement, I elected to not get another Guzzi after the deer killed my Stelvio and reading the recommendations that these bikes are not good for short rides.
Shame because I loved everything about that bike (after all the sorting of "character stuff" was done), power delivery, handling, ergos... :'(
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Data point, I found the "mayo" gunk in the valve cover of my 2V 1200 Sport. During winter. I ride all year, all temps, sans Ice.
Did not see it on the Stelvio (rollers), but because the bike would be my primary transportation all year, and riding only 17 miles of highway in sub-freezing conditions are a requirement, I elected to not get another Guzzi after the deer killed my Stelvio and reading the recommendations that these bikes are not good for short rides.
Shame because I loved everything about that bike (after all the sorting of "character stuff" was done), power delivery, handling, ergos... :'(
With a roller top end it would *Probably* of been fine. In cold weather simply masking off the cooler would probably of been adequate to keep oil temps up to an acceptable level as long as it wasn't raining every time you rode.
Pete
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OK just an update on this topic.
The bike I was dealing with was a 1200 Sport 8V. While I'd had the cams out before and examined everything it must of been failing for a while with no evidence as it was giving me kittens!
Anyway this time around the evidence was there, the factory approved a roller kit for it but they were out of stock as there has been a run on them this spring, (Hmmmmm?). Luckily I had the kit I bought for mine so I was able to use that. It was missing one bit but I was able to canibalise that out of the dead Stelvio.
Finally got it running this morning and what a differenece. It clearly shows that even invisible damage will have an impact on performance. Interestingly the factory has a new map specifically for rollerised Sport 1200's. I uploaded this and also very interestingly the TPS value changed to 7.5 degrees, an almost identical change as we have experienced with Mark's mapping changes. Perhaps the WM guys are learning ;D. A quick re-set of the TPS and self learning parameters and well! What a difference! Idle is still far from perfect but that is probably a result of the trim factors imposed by the closed loop operation. It also seems to be improving as a 20 minute ride made it significantly better.
Thing is the Sport 1200's use a 'Stand alone' cam profile in flat tappet form. The 'C' kit has a 'Universal' profile. That means that a new map would of been essential. Anyway this bike is off to Wagga soon so Mark can Log build a map for it. After that we should have that covered for bikes that haven't been screwed with by fitting junk like aftermarket filters and the like.
I'm glad I finally got to the bottom of it though, I've spent at least a fortnight on this great chunk of munt over the last six months and now, at last, it's running OK.
Pete
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How many 'Home Mechanics' possess Navigator or PADS? While most of us know that you can use a number of aftermarket tools to perform tasks like re-setting the TPS and the adjustable parameters of the ECU the simple fact is the only FACTORY APPROVED way of doing this is with the factory tooling. Don't have access to it? Fine! See you in court! I'm not saying this is necessarily right or fair but I'd say that legally you'd have a hard time pressing your claim. If you can't re-set your TPS you can't correctly balance your throttle bodies. If you don't keep your throttle bodies balanced you are not properly maintaining your bike. QED. Warranty declined. There is more to 'Servicing' a bike than changing its oil and adjusting the valve lash.
Pete
Just catching up on this thread. No dog in this hunt, but your logic re invalidating the warranty for use of aftermarket tools won't fly in the US.
Mag-Moss applies equally here.
A reset tool is no different than a brand of oil, they cannot require their own "brand" as condition of warranty or it must be provided free of charge.
Now it's a different thing if you load a modified map AND they can tie that to a failure, but resetting the TPS and checking/adjusting TB balance, no.
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Now it's a different thing if you load a modified map AND they can tie that to a failure, but resetting the TPS and checking/adjusting TB balance, no.
Don't think tie-ing it could be argued against, that and aftermarket exhausts/ non std air filters etc go under the "fiddled with" clause.
Warranty only has to covers std , but reading between the lines Guzzi are covering all failures regardless of mileage /age.
but only failures, so logical thing to do is ride it till it fails, seems mad not to recall all, but bean counters know only a few bikes get ridden, why fix those that don't break ?
If it were a lock up and throw you off scenario it would be different but very little litigation risk here, just inconvenience of putting it in van.
What happened to RTW Stelvio man of a couple of years ago, did his cams go west ? That was good test
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Don't think tie-ing it could be argued against, that and aftermarket exhausts/ non std air filters etc go under the "fiddled with" clause.
No it has to be directly connected to deny specific coverage under the warranty in the US.
Very few things can blanket void a warranty here, except things like racing it.
If you load a map or change pipes and an AC they can't deny you say coverage of a defective starter or regulator, but they could piston or valve damage if it's connected to the modification (running too lean or even too rich depending on the failure).
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No it has to be directly connected to deny specific coverage under the warranty in the US.
Very few things can blanket void a warranty here, except things like racing it.
If you load a map or change pipes and an AC they can't deny you say coverage of a defective starter or regulator, but they could piston or valve damage if it's connected to the modification (running too lean or even too rich depending on the failure).
This case is slightly different as it's "goodwill" out of warranty claim, Pete said they're covering all 8V that fail.
If the bean counters are onto it, they can and will disclude modified bikes.
Even under warranty, camshaft damage could feasibly be "tuned" related , be a long legal battle to prove it wasn't, tuned to destruction, they'd say. Expensive lawyer to argue.
But if several hundred got their claims knocked back it may be worth it, class action ?
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This case is slightly different as it's "goodwill" out of warranty claim, Pete said they're covering all 8V that fail.
If the bean counters are onto it, they can and will disclude modified bikes.
Even under warranty, camshaft damage could feasibly be "tuned" related , be a long legal battle to prove it wasn't, tuned to destruction, they'd say. Expensive lawyer to argue.
But if several hundred got their claims knocked back it may be worth it, class action ?
I know, I'm not questioning any of that.
I was simply clarifying that it is hard to blanket void a warranty in the US.
It's tangentially related to the thread as the discussion brought it up.
Piaggio is free to do what they want with regards to goodwill after the warranty period.
But for failures that occur in warranty, they can't use simply resetting the tps with Guzzidiag vs. NAV or PADS as an excuse assuming related services were properly performed.
The burden being on Piaggio to demonstrate that it wasn't.
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Or if you want to fly a bunch of giant flags on the rear of your trike , and the clutch fails . Hmm , wonder how a warranty claim would hold up if the rider and passenger were both , er , well , 400 pounders ;D
Dusty
Yeah, that was a weird one, but it was at least arguably related. And I suspect we didn't get all the story in that 15 minutes.
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I know, I'm not questioning any of that.
I was simply clarifying that it is hard to blanket void a warranty in the US.
It's tangentially related to the thread as the discussion brought it up.
Piaggio is free to do what they want with regards to goodwill after the warranty period.
But for failures that occur in warranty, they can't use simply resetting the tps with Guzzidiag vs. NAV or PADS as an excuse assuming related services were properly performed.
The burden being on Piaggio to demonstrate that it wasn't.
I concur
But modifying map, exhaust etc another story, they can use that, not saying they will but they can.
Not using factory tools to rest std parameters would be a very long bow IMHO
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In my experience the importer here is very good and will, as long as the Dealer/Service Agent isn't trying to pull their chain, will go into bat for the customer. Ultimately though it is down to the factory to make the final call and sometimes it's good, sometimes it's bad.
With the failed tappet issues as long as I've been able to provide some sort of record of when services were provided and by whom I haven't had a problem. The only one that was touch and go was a bike from the North Coast of NSW which had no record but even it got a kit because it was an ex importer demo.
Pete
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In Australia the overarching consideration with regard to the law and warranty is "fit for purpose"
In other words even if outside the covered period the product fails in a manner that it should reasonably be expected to not, then the manufacturer is libel because the product hasn't fulfilled its reasonably expected purpose.
So an engine that eats it cams or whatever outside the warranty period but within a period that it could reasonably be expected to still be totally serviceable falls within that criterion.
It's what keeps the manufacturers honest and has them coming to the party with out of warranty issues.That and the obvious good will to the customer and the reputation of the company.
It's not all black and white
Ciao
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Well today I boxed up a load of broken shite and posted it to Denmark!
One of our members who I'm sure will identify himself if he wants to has access to all sorts of boffiny testing machinery and he's going to analyse aome of the crap looking for clues.
Stay posted.
Pete
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Pete, I would like to share the postage in the name of research.
You are sharing the information with us, it is not right for you to bear the cost alone.
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Nah, s'all good. I stuffed two cams. A cambox and a hand full of crappy tappys in one of the boxes the new parts come in and the whole lot weighed less than two Kg so it didn't cost much, really. If we get some useful info we need to buy the bloke who's doing it a swag of beers!
Pete
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Well today I boxed up a load of broken shite and posted it to Denmark!
One of our members who I'm sure will identify himself if he wants to has access to all sorts of boffiny testing machinery and he's going to analyse aome of the crap looking for clues.
Stay posted.
Pete
Should prove useful. ;-T I imagine a factory team has looked into this problem. Are they not forthcoming with their findings? Though, I suppose disclosing that, or not, is their choice.
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Getting any information from the factory is like getting blood from a stone. If I could get any kind of believable answer from that source I wouldn't be bothering to pursue this, believe me.
Pete
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Nah, s'all good. I stuffed two cams. A cambox and a hand full of crappy tappys in one of the boxes the new parts come in and the whole lot weighed less than two Kg so it didn't cost much, really. If we get some useful info we need to buy the bloke who's doing it a swag of beers!
Pete
I'll buy him beers.
My griso (2010) and I are following this thread with a little bit of anxiety.
13.000 km and everything is fine so far. Now it's winter here in Denmark, griso is in hibernation, waiting for more flogging in the spring.
/Steffen, Denmark.
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Couldn't stand back and let this one fall off the front page!
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Well I'm pretty happy with my 08 8v Griso now. It's had four sets of cam gear on re-opened warranties. The last one was fitted in February this year. It's still running -in fact it is going better than it ever has before. I hardly dare say it, but I think they may have fixed it with the roller tappets.
This is the longest I have ever gone without a failure! Coming up to 30k miles. And Guzzi gave me a Termignoni can as a good will gesture!
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Checked with the mg dealer here to see if they could get a roller tappet upgrade for the 09 griso. They checked into it and were told the factory would not release the kit untill the bike failed. Now way to buy one outright. Can anyone say aftermarket?
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Checked with the mg dealer here to see if they could get a roller tappet upgrade for the 09 griso. They checked into it and were told the factory would not release the kit untill the bike failed. Now way to buy one outright. Can anyone say aftermarket?
There's no way that a low production machine like a Guzzi will ever have after market parts like that..
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Checked with the mg dealer here to see if they could get a roller tappet upgrade for the 09 griso. They checked into it and were told the factory would not release the kit untill the bike failed. Now way to buy one outright. Can anyone say aftermarket?
Well they sell them happily to me ??? Not cheap mind.
Pete
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I realize your 100% right about that Chuck in Ind. The dealer also explained that of the 2 failures they've seen, the factory sent them replacement flat tappets to make the repair. They didn't mention if they were the dlc coated type or not. Guess I'll be riding with my fingers crossed for know. 8v roulette, maybe I should check with some other dealers.
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Lucian, ask them to punch 1A002082 into their parts system. That's the 'C' kit that you need if you have an A5 motor. I can get you one easily enough although they're on back order right now. Cost here is $1,739.73 but the exchange rate is really in your favour at the moment. My guess is that it would be cheaper buying from Italy or wherever.
Oh, AF1 have 'em listed at $1486 US so I'm sure any other dealer can get you one if they can be bothered. Give MPH a ring or one of the guys who post here.
Pete
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So what we have here is a flat tappet Guzzi 8V converted to roller tappet? Excuse my ignorance but an 8 valve has pushrods and cam in the V valley ? And the rollers run on the existing flat tappet cam?
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No, overhead cam with flat tappets, like many modern cars.
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No, overhead cam with flat tappets, like many modern cars.
Not a true OHC engine. More like a mid *cam in head* engine.
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Not a true OHC engine. More like a mid *cam in head* engine.
Oh... Like the 60-70's Opel 4 cylinder? So there's a rocker with a cylinder shaped tappet running directly on the cam?....The reason I asked is a roller cam has different lobe profiles than a flat tappet cam....replacing a typical round tappet with a roller will shorten cam duration quite a bit
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So what we have here is a flat tappet Guzzi 8V converted to roller tappet? Excuse my ignorance but an 8 valve has pushrods and cam in the V valley ? And the rollers run on the existing flat tappet cam?
I'm pretty sure the conversion kit comes with a newly designed cam, for roller use. Someone,(Pete), can confirm.
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Oh... Like the 60-70's Opel 4 cylinder? So there's a rocker with a cylinder shaped tappet running directly on the cam?....The reason I asked is a roller cam has different lobe profiles than a flat tappet cam....replacing a typical round tappet with a roller will shorten cam duration quite a bit
I believe there's a stubby length pushrod between the lifter and rocker. I saw an exploded view once or twice, so not an expert. :) Absolute zero familiarity with the Opel.
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Oh... Like the 60-70's Opel 4 cylinder? So there's a rocker with a cylinder shaped tappet running directly on the cam?....The reason I asked is a roller cam has different lobe profiles than a flat tappet cam....replacing a typical round tappet with a roller will shorten cam duration quite a bit
The roller cams are completely different to the flat tappet cams but their two profiles produce identical lift and duration figures at the valve. Hence the fact that they run the same mapping. The exception to this is the 1200 Sport which had 'Stand alone' flat tappet cams but the conversion kits use the same cams as all the rest of the models. The factory has released a 'Stand alone' map for converted 1200 Sports which they insist is for that model alone. This is quite funny as if you look at it with Tunerpro you find its the 2008/9 Stelvio map re-badged.
I've posted up the parts diagrams for both roller and flat top ends before but can do it again if you can't find them.
Pete
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So you're also replacing the cam... I missed that part...
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When you do a conversion you swap everything North of the cylinder head bar the rocker cover, the rockers themselves and camchain sprocket. The kits consist of various parts, some engines needing shims installed under the inlet valve springs to add preload as the roller tappets are appreciably heavier than the flatties and their pushrods.
The major components though are the camboxes which are delivered to you as an assembly. It is essentially the same set-up as the Cali 1400, it even uses the same cambox casting with the extra spark plug tunnel. It's just machined so it doesn't interfere with the single plug 1200 rocker covers. The roller cams are also pre-loaded by a Belville washer assembley on the front of the cam that acts against the front of the cambox casting rather than the older internal shimming or, on the early engines, nothing to stop the cams lashing around and making a ghastly noise! :D
Here's a couple of pics of the early flat tappet camboxes which include the rocker supports and various other bits.
Cambox on bike.
(https://farm4.staticflickr.com/3310/3430837542_412370acf9_z.jpg) (https://www.flickr.com/photos/44512000@N00/3430837542/)
Off bike and being reassembled after the early cam/tappet swap.
(https://farm4.staticflickr.com/3347/3430189113_ee022183c3_z.jpg) (https://www.flickr.com/photos/44512000@N00/3430189113/)
Eeny-weeny pushrod. (Just for giggles I got our local Jewler to turn a pair of these now redundant items into ear-rings for Jude. They're a bit heavy mind but you wouldn't wear them every day! ;D)
(https://farm4.staticflickr.com/3317/3430985234_3ce605fec0_z.jpg) (https://www.flickr.com/photos/44512000@N00/3430985234/)
Roller cambox on engine.
(https://farm8.staticflickr.com/7474/15710137689_9129b990ca_z.jpg) (https://www.flickr.com/photos/44512000@N00/15710137689/)
And off the bike and showing the location of the 'Pads' that sit atop the 'Pusher' on the roller tappet. This fits into the cup on the rocker and mimics the top of the eeny weeny pushrod.
(https://farm6.staticflickr.com/5168/13883328039_f7ccab27b2_z.jpg) (https://www.flickr.com/photos/44512000@N00/13883328039/)
Pete
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So you're also replacing the cam... I missed that part...
to show how it was made at first:
(http://fastguzzi.nl/gallery/main.php/d/4318-1/8vtech14_001.jpg)
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I've haven't been here for a while because I sold my 1200 2v Sport and bought a Triumph Tiger Sport in November but I'm missing the Guzzi already so If I can find another I'm back in the fold pronto.
Before the Triumph I went to my local Guzzi dealer and we had what can be described as a honest and frank discussion about me buying a 8 valve Sport.
The discussion came down this. He believed the 8 valve flat tappet motor has a design fault that can only be solved with a roller conversion. He offered to sell me a Sport and straight away put in a warranty claim for roller cams because he had no faith in the existing design. Even then he would only be happy when the roller motors had racked up some decent mileage without problems.
The guy had boxes of old cam assemblies and talked me through what he beieved was the cause he was even fitting roller cams at cost to keep his customers on side.
I just couldn't bring myself to buy a new bike and then go through a warranty claim without even riding it hence the Triumph.
The Triumph is a good bike but the soul is missing. If Guzzi had not shot themselves in the foot with the 8 valve motor I would still be amongst a great bunch of people on this forum, a crying shame for me.
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There are a LOT of working higher mile 8V flat tappet motors out there to be THAT paranoid.
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Interestingly Mark III who posts here had his go out. His was an interesting case because his bike was sent from the factory with a Japanese market header pipe on the RH side. This pipe had an extra catalytic converter in and one of the things he noticed with it was that the RH head always ran substantially cooler than the left and, especially in cooler weather, was always full of Mayo.
When the tappets went tits and I rollerised it it was interesting to note that LH tappets, although showing damage were nowhere near as worn as the RH ones which were totally trashed.
No, it's not a definitive proof but it does correspond with my belief that the problem is related to over-cooling and moisture in the oil.
Until this spring I had NEVER had a Tappet failure through my shop. This year I've had half a dozen. Last winter was very cool and damp. Coincidence? I think not!
Pete
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I've haven't been here for a while because I sold my 1200 2v Sport and bought a Triumph Tiger Sport in November but I'm missing the Guzzi already so If I can find another I'm back in the fold pronto.
Before the Triumph I went to my local Guzzi dealer and we had what can be described as a honest and frank discussion about me buying a 8 valve Sport.
The discussion came down this. He believed the 8 valve flat tappet motor has a design fault that can only be solved with a roller conversion. He offered to sell me a Sport and straight away put in a warranty claim for roller cams because he had no faith in the existing design. Even then he would only be happy when the roller motors had racked up some decent mileage without problems.
The guy had boxes of old cam assemblies and talked me through what he beieved was the cause he was even fitting roller cams at cost to keep his customers on side.
I just couldn't bring myself to buy a new bike and then go through a warranty claim without even riding it hence the Triumph.
The Triumph is a good bike but the soul is missing. If Guzzi had not shot themselves in the foot with the 8 valve motor I would still be amongst a great bunch of people on this forum, a crying shame for me.
If there wasn't internet you would have the 8V. And if there wasn't internet there had never been a roller kit.
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I'm not sure about that Paul I may have bought a 8V Sport in ignorance but with the problems the bike has suffered in the U.K. I probably wouldn't have kept it long.
My local Triumph dealer will no longer take Moto Guzzis in part exchange the last 8V Griso they sold cost them a lot of money in cam repairs under their own warranty scheme.
I'm doing my best not to be negative and I certainly would buy a roller cam model but Guzzi did not offer the 1200 Sport with rollers for some daft reason and it is no longer available anyway.
Guzzi should have recalled all problem engines for roller conversions, suffered the financial pain but kept their reputation intact. But like other manufacturers unless it is safety related they bury their heads in the sand. This isn't unique to Guzzi but the 1200 8V motor is a big proportion of the model range so the brand suffers more as a consequence.
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What I like about Guzzis is there always a bit of enigma about them. I have been phoning round U.K. dealers to see what 1200 2v and 8v Sports are available and had some interesting conversations.
One guy who was on the phone 30 minutes talking about 8v engines swore blind that by using Motul 7100 he has had no cam failures on any bike he has sold. He had no 1200 Sports left and was 300 miles away so he had nothing to gain from me. He was convinced the ester in the Motul oil made all the difference. Keeps the mystery going a bit longer I suppose. http://chemlube-malaysia.blogspot.co.uk/2012/11/the-benefit-of-ester-based-synthetic-oil.html
Still looking for a 1200 2v with low mileage though.
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Given the fact that the 1200 Sport hasn't been manufactured since early 2013 none of them were ever made with the roller top end. They all require the 'C' kit to convert to rollers as the Sport used a 'Stand Alone' cam profile for some reason and then the map needs to be updated to a 'Special' map for the rollerised motor. Only thing is it isn't a 'Special' map, it's just the 2008 Stelvio map re-named ::). None of the Sports have shimmed valve springs either.
Oh, and on the oil issue? Yes, using a full ester synthetic is vital. It's obvious if you understand how the engine cools itself.
Pete
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I don't want to flog a deceased horse here, and, there was a question about warming up the motor by idling. Now this is something I never do with vehicles, and I have no idea how this would play out with an oil cooled Guzzi, but I can relay a story from my BMW days:
An owner of an 1150 GS purchased the BMW official factory shop manual and was preparing for an oil change. The factory service manual specified warming up the motor for 20 minutes by letting it sit idling, which the owner did unattended in his driveway. He came back after 15 minutes to find his bike on fire, the motor had gotten so hot that the oil site glass had popped out and hot oil dumped on the exhaust manifold and ignited. BMW NA eventually replaced his bike. I don't know if they ever corrected the service manual. My experience with the oil cooled BMW was that it got hot really quickly when idling, so much so that a large fan was recommended to keep it cool if a throttle body sync would take more than a minute or two. Certainly the bikes overheated in traffic and had to be shut down if stopped for an extended period. No fan on the oil cooler. Worse in the summer but still an issue in the winter.
Back to the dead horse: no idea if this applies in Guzziland.
And a question about the living horse: is the warmup (or winter overcooling) issue specific to the Griso, or does it also apply to the Norge? Different radiator and air flows involved.
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All the 8V's over-cool in weather below about 15*C and if it's wet? Forget it, the oil temp won't get much above 55-65*C. Perversely, there are points in the motor, most specifically in the cooling galleries around the exhaust valves, where the oil temperature will momentarily reach very high temperatures. Hence the need for a full ester synthetic oil.
If you leave any air/oil cooled engine idling for a long period it will overheat. I have a customer who cooked his Griso this way. There was surprisingly little damage to it though inside the engine.
Pete
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Given the fact that the 1200 Sport hasn't been manufactured since early 2013 none of them were ever made with the roller top end. They all require the 'C' kit to convert to rollers
Pete
Pete one half of the 1200 sports 8v needs the C kit, other half the D kit. Depending on production date and easy to see on head cover.
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I'll have to double check the bulletin. I thought they all needed the 'C' kit.
I stand corrected. The later ones need the 'D' kit. Apologies.
Pete
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Oh, and on the oil issue? Yes, using a full ester synthetic is vital. It's obvious if you understand how the engine cools itself.
Pete
That's interesting you agree on the ester content Pete because it's the first time I have heard of it here or anywhere else.
I also didn't realise not all fully synthetic oils contain ester.
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Well I've been very vocal about it for years Dave.......
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From what I've seen, the 'full ester' oils will say so on the bottle; other full synthetics tend to be a bit coy about base stocks. I have a 2V engine so I don't think the ester bit matters as much (although I run a full ester oil—it's my baby!).
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New slogan for Moto Guzzi: If you don't want your engine to take a siesta, make sure when you buy oil, on the label you see ester.
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Or even: ester la vista baby.
https://www.youtube.com/watch?v=Q73gUUr8Zlw