Just in time!

[rodekyll]

Pedantries are not suffering abuse at the hands of the uncaring , unlike the poor Naugas whose pores are apparently water proof in the poring rain . However the plight of the marquees , at least in America, is unprecedented in the annals of history . Mark my words , this is a sign of the decline of Western civilization .

  Dusty

 

Not the entire civilization, just the feudal system part.  Long live the Marquis!

(yes, you clicked on a new page for this.)

[Moto]

Rollerised my Griso this morning. I thought it had been behaving a little less enthusiastically recently and sure enough the tappets were just beginning to fail. 90,000Km, not bad . Bloody glad I bought my C Kit a couple of years back. They are not stock her at the moment.

All back together and good as gold now!

Pete

Wow, it really is the best of all possible worlds, huh?

If I were lucky enough to notice a "little less" enthusiastic performance and open up the motor before disintegrating parts fouled the bearings and oil passages, and lucky enough to have purchased (on my own nickel) the needed kit so that the non-availability of parts when the failure occurred was no problem, then I'd be happy too, I guess. But not happy about the expense and inconvenience at 55,000 miles. And not happy at all if I were not as lucky as you.

Makes me glad to have stuck with the 2-valver, and makes me resolve to avoid the flat-tappet 4-valve model if I ever make the transition!

Keep smiling, Pete!

Moto

[MotoG5]

Damn spell check. 

[MotoG5]

Every night before I go to sleep. Lannis, Oldbike54,rodekyll,Dusty..................

[oldbike54]

Every night before I go to sleep. Lannis, Oldbike54,roadkill,Dusty..................

 Hey , I am but a mere servant to the comedic needs of WG 

 Marquis , another word Mercury couldn't pronounce correctly .

  Dusty

[Vasco DG]

Interesting development. Just took bike out for a gallop and it's going to need a new map. Although Guzzi use the same GRS8V-03 map for both flat and roller tappet bikes running open loop there are obviously big differences in how the engine is breathing.especiall y at the top end. Some logging work will tell the story but probably the last 15% or so of throttle, especially in the lower gears, it's like running into a brick wall! Feels like it's going lean but I'm not going to call that,I'll wait for the log data.

Pete

[Vasco DG]

Wow, it really is the best of all possible worlds, huh?

If I were lucky enough to notice a "little less" enthusiastic performance and open up the motor before disintegrating parts fouled the bearings and oil passages, and lucky enough to have purchased (on my own nickel) the needed kit so that the non-availability of parts when the failure occurred was no problem, then I'd be happy too, I guess. But not happy about the expense and inconvenience at 55,000 miles. And not happy at all if I were not as lucky as you.

Makes me glad to have stuck with the 2-valver, and makes me resolve to avoid the flat-tappet 4-valve model if I ever make the transition!

Keep smiling, Pete!

Moto

Which makes PERFECT sense! While I would suggest that if one can afford it buy a new roller tappet model or a second hand one if you can find one I would also suggest that if you're buying a flat tappet bike don't even think of buying one that doesn't have a full service history. While the factory recommendation of a 'Rinse' of the sump is absurd and at the very least the sump needs dropping and the filter replacing and preferably a look at the oil pumps if the damage has gone any distance.

It never really worried me because I WANTED to find out the how and why of why things were failing. I've done that to my satisfaction and I'm not going to argue with pinheads who have done no research. The only way to find out how and why stuff breaks is to test it to failure. Given the problem I was dealing with and the fact that for a long time I couldn't get a flat tappet motor to fail all I could do is gather data and I archive it. Once I actually started seeing the problem first hand I could get it investigated properly. Apart from the factory and maybe not even they, nobody I don't think has done as much research into this as I have and I've got to the stage now, as probably have some others, of knowing the tell-tale signs of failure long before the rattling starts. What I find amazing is that there are reports of people riding 8V's to the point where the tappet feet completely eroded away and the pushrods dropped through and smashed the camboxes! I mean how could you possibly do that? Apart from the noise the performance would of been abysmal and the oil would be so rapidly fuel diluted that the entire engine would be close to toast!

Pete

[lucky phil]

What I find amazing is that there are reports of people riding 8V's to the point where the tappet feet completely eroded away and the pushrods dropped through and smashed the camboxes! I mean how could you possibly do that? Apart from the noise the performance would of been abysmal and the oil would be so rapidly fuel diluted that the entire engine would be close to toast!

Pete

I guess the same sort of Muppet that can ride a twin cylinder motorcycle around on one cylinder with the resultant 65% reduction in power and only complain about the fact it wont idle anymore.

Ciao

[pete mcgee]

Yeah, I covered it before but I'll PM you as I don't think I could stand having to listen to another five pages of blithering hysteria if I post 'em up again.

Pete

Looking forward to it, when you get the time.
Thanks.

[Moto]

It never really worried me because I WANTED to find out the how and why of why things were failing. I've done that to my satisfaction and I'm not going to argue with pinheads who have done no research.

Your persistent attention to this problem and your sharing of your findings have been of great benefit to us all! Many thanks.

Moto

[Moto]

So, one KM=1.609344 miles.

And..1 km = 1.62 miles

Ha! You're both wrong. 1 km = 0.62 miles! And 1 mile = 1.61 km. (Approximately.)

I hate dealing with this crap, and wish we'd all go metric. In the meantime I use 0.62 and 1.62 as my off-the-cuff conversions, so I can just remember one set of values after the decimal place, "62".

Doing this, I also remember that the Golden Ratio, phi = 1.6180339887..., is the only positive number whose inverse, 0.6180339887..., is zero followed by the identical values after the decimal. So I save brain cells by remembering 1.62 as approximations for both the Golden Ratio and the mile-kilometer conversion factor, and 0.62 for their inverses, leaving other memory locations free for remembering where I put my tape measure, if I ever find it again.

MotoG5 gave the right numerical answer for the number of miles corresponding to 90,000 km, though.

[Lannis]

Every night before I go to sleep. Lannis, Oldbike54,rodekyll,Dusty..................

Like counting sheep; puts you right to sleep!    Glad to be of help ....

[kirby1923]

Ha! You're both wrong. 1 km = 0.62 miles! And 1 mile = 1.61 km. (Approximately.)

I hate dealing with this crap, and wish we'd all go metric. In the meantime I use 0.62 and 1.62 as my off-the-cuff conversions, so I can just remember one set of values after the decimal place, "62".

Doing this, I also remember that the Golden Ratio, phi = 1.6180339887..., is the only positive number whose inverse, 0.6180339887..., is zero followed by the identical values after the decimal. So I save brain cells by remembering 1.62 as approximations for both the Golden Ratio and the mile-kilometer conversion factor, and 0.62 for their inverses, leaving other memory locations free for remembering where I put my tape measure, if I ever find it again.

MotoG5 gave the right numerical answer for the number of miles corresponding to 90,000 km, though.

Ooops,
Yes when I reread my post I caught that and changed it. 39000"= 3250 ' (rounded from 39.375 or 3281.25)

[56Pan]

Your persistent attention to this problem and your sharing of your findings have been of great benefit to us all! Many thanks.

Moto

 :1: Second that.

[steffen]

:1: Second that.

:1: third that

[Lannis]

Your persistent attention to this problem and your sharing of your findings have been of great benefit to us all! Many thanks.

Moto

I agree wholeheartedly with that.   

I find the finding (if I can say it that way) that a modern street motorcycle engine was built with flaws that make it unlikely that will go farther than 50K miles, however, without destroying itself, unsettling to say the least.   

I really appreciate the effort that goes into finding these things out.   I also appreciate the oft-unappreciated effort that goes into publishing the results for all and sundry to see.    I don't, though, agree that such performance is just part of what we should expect if we want to have fun with our motorcycle.   These aren't race-bikes, or 80 HP 250cc screamers; they're overbuilt, heavy-duty Moto Guzzis .... and if Ambassadors and T3s had gone this way, Moto Guzzi really WOULD have successfully offed themselves in about 60 years from 1921, instead of still being around ... for awhile. ...   

Lannis

[LowRyter]

perhaps some baseline-ing would help?

1.  Are all 8V engines subject to this problem or only certain models (such as Grisos after 2012)

2.  Does it make sense to go ahead and change out the parts at 50k miles rather than encounter a potential failure?

3.  How does one obtain these parts and where are the reputable shops?

Reading the thread, I find these questions the simplest way to navigate this issue.  I have no dog in the fight.  I can understand how an owner would not be happy with this scenario.  Fixing the problem, quick, cheap and easy will go along ways to mitigating it.

[Lannis]

perhaps some baseline-ing would help?

1.  Are all 8V engines subject to this problem or only certain models (such as Grisos after 2012)

2.  Does it make sense to go ahead and change out the parts at 50k miles rather than encounter a potential failure?

3.  How does one obtain these parts and where are the reputable shops?

Reading the thread, I find these questions the simplest way to navigate this issue.  I have no dog in the fight.  I can understand how an owner would not be happy with this scenario.  Fixing the problem, quick, cheap and easy will go along ways to mitigating it.

I'd love to hear informed opinions on those questions myself.    I don't believe in dog-fighting, though, so I'm trying to figure out another metaphor .... 

Lannis

[Poncho]

I hate dealing with this crap, and wish we'd all go metric.

No, we should never give up our last bargaining chip. We will all convert to metric when all the Queens subjects change to ride on the correct side of the road.. that would be the Right thing to do. poncho

[Kent in Upstate NY]

How about "I don't have any skin in the game"?

[biking sailor]

perhaps some baseline-ing would help?

1.  Are all 8V engines subject to this problem or only certain models (such as Grisos after 2012)
Actually 8V engines before approx. late 2012, when they changed over to rollers from the flats (why I made sure my 2013 Stelvio had rollers).

2.  Does it make sense to go ahead and change out the parts at 50k miles rather than encounter a potential failure?
Yes, in my opinion, because of the "hard bits" that can get in bearings and oil pump and such in the bottom end that could compromise their life and be very costly to clean out or repair.

3.  How does one obtain these parts and where are the reputable shops?
That's the problem, some of the correct kits are very hard to get in some locations (others may be able to shed more light here with their experiences) and I think we all know where "good dealers are (if I had one that needed major help, it would be hauled down to Houston    )

Reading the thread, I find these questions the simplest way to navigate this issue.  I have no dog in the fight.  I can understand how an owner would not be happy with this scenario.  Fixing the problem, quick, cheap and easy will go along ways to mitigating it.

[Lannis]

How about "I don't have any skin in the game"?

That's a good one.   Except, with a 2009 Stelvio, I may have a LOT of skin in the game.   Or chips on the table ..... (Hey!)

Lannis

[LowRyter]

Darren 

[ohiorider]

Aside from the switch from flat to roller tappets, didn't Guzzi 'improve' the quality of the flat tappets a year or two after Griso 8v production began?  At the time I purchased my 2012 Griso, I was under the impression that the original 'problem' had been cured.

[kirby1923]

Mostly we have converted , it is only us serfs that are still saddled with the illogical system based on the length of some ancient dudes arm  Maybe the aristocrats had twelve fingers back then

  Dusty

A hard transition for me but done.

So you think the length of some ancient dudes arm is better than the 18th century estimation of the distance from the equator to the north pole!!! BTW how did they know where the north pole was?

Oh, at the Top of course!! or in the middle for the flat earth types.

nevermind!
mike

[oldbike54]

 

 Wait , what , the Earth isn't flat ? Have the authorities been notified 

  Dusty

[kevdog3019]

I'm often not convinced the factory got it right. 

[drw916]

Those are good questions.  I have 30,000 miles on my 2010 Stelvio.  Am I good for another 30k?  More?
No need to worry?

I'm not about to get rid of it, but If it is inevitable, I would like to plan on when so I have some control.  Although if it has to fail first that all goes out the window. 

I'm not smart enough to hear the difference in the bikes running, and wouldn't know what to look for when adjusting the valves.

[Vasco DG]

Aside from the switch from flat to roller tappets, didn't Guzzi 'improve' the quality of the flat tappets a year or two after Griso 8v production began?  At the time I purchased my 2012 Griso, I was under the impression that the original 'problem' had been cured.

Original tappets were chilled cast iron and some were poorly heat treated and failed, (Once again I NEVER saw this problem in my workshop.). In about 2010 they introduced a new design of forged steel with a Diamond Like Carbon, (DLC) coating on them. This was pretty innovative as I don't think it had previously been used on production tappets but Guzzi has a long history of innovation and early adoption of new technologies so I wasn't *Surprised*. Unfortunately the choice was poor as it had been found that there were problems getting the DLC to adhere to a ferrous substrate but more importantly it is very sensitive to use of the correct lubricant and it doesn't withstand high impacts well. Poor servicing and the wrong or contaminated oil and failure is inevitable. The fact that the 8V is grossly over-cooled greatly exacerbates the problem due to degradation/contamination of the lubricant. Too wide valve lash adjustment leads to the opening flanks of the cam crazing the DLC creating further issues. (I posted some pics taken using an electron microscope up a few months ago where this degradation was clearly visible.)

Use the right lubricant, service your bike properly and the tappets can last a very long time. They usually seem to fail around the 30,000 km mark, mine soldiered on until 90,000 but interestingly when I did the swap my rocker covers were full of mayonnaise, something I have rarely seen before and I have no real explanation for as I have always adhered to a very strict regime of not starting it unless I'm going to get it really hot! Once the DLC is compromised it can fail completely in as few as fifty cycles!

As to what to do about it? Well I was able to pick the change in my engine's performance immediately and did something about it. Yes, I'd bought a kit a couple of years ago, (Not cheap, cost over one and a half grand back then but I didn't want to be stuck like others are now if my bike went tits and there were no kits available. It seems though that either a lot of people are ridiculously thick skinned and insensitive or they have the sort of attitude that says 'This is a newish machine it can't be going wrong so I'll ride it to death' and then complain that it's terribly broken. Sorry but I find this attitude bizarre! Anyway the tell tales are there I currently have a bike in my workshop that was traded in to Canberra Motorcycle Centre that I was asked to look at for a prospective buyer. I knew as soon as it fired up it had done its cams, told the salesman, he was skeptical so I just said "See Ya!" and started to walk away. His boss called me back and when the rocker covers came off I was able to show him the evidence and they (Grudgingly.) gave it to me to fix. It's been clogging up my workshop like a huge, black, turd for two months!

I do find it frustrating that the kits are out of stock, (I think we are currently looking at a six to eight week delay!) but that is something that nobody seems to be able to do anything about. Why I don't know. Batch production and low volumes I would guess? And now of course we have August looming on the calendar! That's life though.

At the end of the day to me the hassle is worth it. I love the 8V engine, it is to me something that is nowadays very rare in a motorbike. A motor that is raw, organic and visceral. It isn't the lightest or the most powerful power plant available, nor is it in the lightest or best handling chassis but for ME and certain others it presses buttons that nothing else available does. I'm willing to put up with a bit of inconvenience for that experience. If you're not? Fine! No skin off my nose. Go and buy something else but fer gods sakes stop wingeing and carrying on like a big girl's blouse.

Pete

PS the other really easy way to pick it is to sniff the oil.

[Steph]

So to recap, the used market will fill up with used 8V bikes, new owners will be presented with mega repair bills if the parts are available.