Chrome bores...

[frozengoose]

This showed up as a pop up one day. Not sure what site I was on, but I guess it was cause Google tracks your searches and brings up similar stuff. Anyone familiar with this:

https://en.powerseal.nl

My interest was piqued because I have an 850T with what I assume are original chrome bores. Never realized this was an issue until I hooked up with this blog a few months ago, so now of course it dominates my thoughts. It was with some trepidation that I dumped the oil this fall, but it looked fine. Also pulled the valve covers but nothing there either, so there's that.

So then, a couple of questions...

1. (or A as Click and Clack would say) What really is the chance that they're be a catastrophic problem? While it's not a garage queen, I have several other bikes to ride, and only put a couple of hundred miles a year on it.

2. (or B) What is the option of going with an over bore kit? It seems to me that if you're going to go to all the trouble of replacing the cylinders, pistons, whatever, you might as well pick up some low end torque, which is what I'm told is the big advantage of the larger motor.

So anyway, appreciate your ideas, keep your thoughts on my heritage to yourself. Thanks!

[Testarossa]

Does the bike have an oil filter? If not, when was the last time you dropped the sump? If it does have a filter, cut the filter open and inspect for chrome. Maybe you're lucky.
You can buy a 950 kit from Gilardoni but it requires balancing the crank, so plan a complete rebuild.

[frozengoose]

Does the bike have an oil filter?
You can buy a 950 kit from Gilardoni but it requires balancing the crank, so plan a complete rebuild.

OK, I'll drop the sump and check it. Early T so no oil filter.
Didn't realize that you had to rebalance the crank, thought it was just a swap for the bigger cylinders/pistons. Thanks for the reply.

[pete roper]

You don’t have to rebalance but it will vibrate a bit more. If I were you I’d see if I could get some 850/83mm Gilsrdonis as the 850’s are a sweet motor. Keeping the chrome bored is playing Russian Roulette with most of the chambers loaded.

[frozengoose]

OK, not what I really want to do, but life, as they say, is change. Appreciate your reply.

[Dave Swanson]

I see that MG Cycle is out of the stock bore Giladorni cylinder/piston/ring sets.   Last week Scrambler Cycle had some in stock but are now out of stock.  Give them a call maybe they have a source https://scramblercycle.com/collections/guzzi-engine/products/moto-guzzi-eldorado-850t-t3-83mm-gilardoni-piston-cylinder-kits-with-head-gasket?variant=2113611071512

Also call Harper's.  Curtis may have a set on the shelf.


Chrome bores will eventually fail and in turn will ruin your motor. 

[Chuck in Indiana]

but it will most likely still run.

Oh, yeah.. it'll continue running until it trashes the bearings, valve train, and oil pump. It will eventually make Pete's "Dogga dogga" noise, and make if fine anchor for a boat.. if the boat is fairly small.

[Antietam Classic Cycle]

A reliable source told me months ago that 83mm bore Gilardonis were done - no more to be produced. If you can find a pair in stock anywhere, buy them. Otherwise your choices as I see it are:

1. iron liners - LA Sleeve can do these. This would be the last resort for me.
2. have the original cylinders replated in "Nikasil" by Millennium or US Chrome. This is only an option if the original pistons are reusable or you can find good replacement pistons. Mark @ Moto Guzzi Classics has new CP pistons.
3. "big bore" kits - HMB in Germany sells 88 mm cylinder kits that are "bolt on", no crank balancing or case machining necessary. However, they do such a pi$$ poor job of packaging parcels that whatever you buy from them will likely end up damaged or will have escaped the box and been lost. MG Cycle did offer 88 mm cylinder sets that already had the "spigot" of the cylinder turned down, but the piston assemblies would still be heavier than stock, so lighter pins and weight removed from the piston itself may be necessary to get them to weight the same as the 83 mm pistons assemblies (and they still might not).

The easiest is really going to be #2 - send the cylinders to be replated, buy new rings and piston pin circlips.

[Two Checks]

While you're at it check the timing chain and tensioner. My T w/filter had chrome and chain tensioner bits in the rocker shaft oil holes.
That's how it was when I got it.

[Rusnak_322]

I would send an oil sample out to a lab like blackstone first. pay $28 to see if there is any reason to be worried.

zkzqb))%2f" class="bbc_link" target="_blank" rel="noopener noreferrer">https://www.blackstone-labs.com/products/free-test-kits/?session-id=22rjjsrc5wjw3riveq4zkzqb&timeout=20&bslauth=&urlbase=https%3a%2f%2fwww.blackstone-labs.net%2fBstone%2f(S(22rjjsrc5wjw3riveq4 zkzqb))%2f

if there isn't a bunch of chrome in the oil, and you are not putting tons of miles on it, then why tear apart a fine running motor?

[Antietam Classic Cycle]

"Denial is more than just a river in Egypt". 

[Testarossa]

How many miles on this bike?  It is a very sweet engine and worth renewing without a displacement increase.

If significant miles (more than 40,000?) here are the big issues:

1. Chrome chips and possible bearing damage. Oil sample to Blackstone labs is a great start. With the sump off, see if there's any wiggle in the con rod big-ends -- better, pull off a rod cap and look at the condition of the bearings and journal (it's possible that scoring of the bearings might not produce wiggle you can feel). If there's serious scoring or the bearings or journal are out of spec, the cam bearings, oil pump and timing chain may also be out of spec. With the cylinders and sump removed, it's easy to pull the con rods and replace the bearings -- if you go that far might as well check the rod-piston balance. Improvement there can make the engine run smoother, noticeably.

2. Rubber dust from the original timing chain tension block. This stuff goes through the oil passages and accumulates in the sludge trap (built into one of the crankshaft weights). If left in place the rubber block will continue to erode and eventually may plug up an oil gallery somewhere. Best to replace the block with a blade-style chain tensioner. While you're at it it doesn't cost much to replace the timing chain.

If you decide to do all this stuff yourself you'll need a few special tools to take off the big castle nuts etc. With a little research you can probably find the tools for around $100. Workshop manual of course. You'll find several threads on this site describing the rebuild of 850 engines -- here's mine: https://wildguzzi.com/forum/index.php?topic=96442.0

[canuck750]

"Denial is more than just a river in Egypt". 

I suggest we add a FAQ to the site headline - Re: Chrome Bores - should I replace them?  YES

[Perazzimx14]

Not knowing what you paid for the bike but if it was around $1,000 or more the added cost of replacing the chrome bores will most likely make you upside down on your purchase. The down side is if you go to sell the with the chrome bores many like myself will only pay non-runner type money (a couple hundred dollars) because we know the minimum cost to get rid of the chrome bores and the costs if the chrome has flaked and the motor needs a complete overhaul. So we go in as guarded as possible. If you continue to run the bike and the chrome flakes that will devalue it to the point where you are better off selling it part x part. This is a huge PITA and takes forever. Sound like a no win situation? It is! Welcome to the wonderful of chrome bore Guzzi's. 

As a side note if Gilardoni piston/cylinders kits are no mas these bikes that's going to suck. I've used Gilardoni kits and also have had cylinders stripped and replated the latter is so much more of a hassle that its to the point where these bikes are not even worth fooling with.

[Two Checks]

You can always send out the cylinders to be resleeved with iron liners or nikasil lined by one of the cylinder rebuilding services.

[Perazzimx14]

You can always send out the cylinders to be resleeved with iron liners or nikasil lined by one of the cylinder rebuilding services.

As Charlie mentioned IF your pistons are reusable. Plus there is added cost of about $40 each way for shipping/packing/insuring because you need to package the stock cylinders like faberge eggs or deal with broken fins.

If you send to Millennium they will reuse your packaging to send the replated cylinders back to you the same way you packed them. So it got to be simply to replicate and sturdy. I ended up buying a sheet of 1" polyiso insulation cutting it on the table saw to make a box that fit the cylinder perfectly.  The I put into a bigger cardboard box and infilled it with more ply's of polyiso, bubble wrap and packing peanuts. Packaging alone cost me about $30.

[Shorty]

Push comes to shove, buy a low mile G-5 or Convert and transplant the engine. Steel lined cylinders, small bump in power.

[Rusnak_322]

Not knowing what you paid for the bike but if it was around $1,000 or more the added cost of replacing the chrome bores will most likely make you upside down on your purchase. The down side is if you go to sell the with the chrome bores many like myself will only pay non-runner type money (a couple hundred dollars) because we know the minimum cost to get rid of the chrome bores and the costs if the chrome has flaked and the motor needs a complete overhaul. So we go in as guarded as possible. If you continue to run the bike and the chrome flakes that will devalue it to the point where you are better off selling it part x part. This is a huge PITA and takes forever. Sound like a no win situation? It is! Welcome to the wonderful of chrome bore Guzzi's. 

As a side note if Gilardoni piston/cylinders kits are no mas these bikes that's going to suck. I've used Gilardoni kits and also have had cylinders stripped and replated the latter is so much more of a hassle that its to the point where these bikes are not even worth fooling with.

Exactly. You could spend $1,000 after all is said and done doing the labor yourself by the time you add in tools and other "while your in there" items and add $250 to the value of your motorcycle.

if it hasn't been sitting for a years, a 45 year, old well running motorcycle is not really going to explode immediately.  This is especially true if you are just putting around as a second or third bike.

I am all for PM, I just spent $1,000 on a timing chain for my wife's Audi A4. But if I were in your shoes, I would get the oil lab work  done and keep an eye out on eBay and craigslist for a later 1,000cc motor or parts bike. You would get the bigger torque numbers and an electronic ignition upgrade.

[Perazzimx14]

Push comes to shove, buy a low mile G-5 or Convert and transplant the engine. Steel lined cylinders, small bump in power.

Push comes to shove, push the T into the garage and shove it into a corner while you enjoy the moderness of triple disc brakes of either the G5 or Vert.   

[Dave Swanson]

Frozengoose.  Check out this thread in the rebuild section.  It is directly applicable.

https://wildguzzi.com/forum/index.php?topic=102453.0

[frozengoose]

Thanks for all the replies. I realize that this is an old topic to some and maybe has been beaten to death in the past. But as a relatively new member, I hadn't seen those earlier posts, so appreciate those who took the time to educate me and provide helpful links without references to my ignorance.

Right now it's snowing, we got about 3" overnight with more expected, so will soon fire up the tractor and start plowing. The T won't move out of the garage for the next 6-7 months, so gives me time to ponder the solution. I will contact some of the service providers and see what's what.

For those who asked, the T has exactly 15,555 miles on the speedometer, but it wasn't working when I bought it in 1989. Turned out to be a broken inner cable, but didn't realize it for awhile, so I'd guess it has maybe 20,000. Engine runs great, has lots of power, and doesn't smoke or use oil.
 
As to cost, I paid $1,500 for it in 1989. Not sure what it's worth now, but certainly not a parts bike in my mind. I've never seen a Guzzi on CL for less than $3000 up here, but then Alaska is different than the lower 48, with limited options for buying any vehicle, unless you want to travel outside to pick one up. So I'm not angsting over the cost as much as to whether it's worth my time and trouble given how little I ride it now. As to getting a newer, better bike, the T suits me fine. Plenty of power, well it could use a little more low end torque, cruises fine at sixty or so, which is my "old man's speed" now a days, and makes a great sound with those Franconi? mufflers.

So thanks again for all the comments, I'll let you know when something happens.  Jon

[Muzz]

Oh, yeah.. it'll continue running until it trashes the bearings, valve train, and oil pump. It will eventually make Pete's "Dogga dogga" noise, and make if fine anchor for a boat.. if the boat is fairly small.

A difference here obviously between the Aussie and Kiwi donks.  Ours tend to go "knocka knocka instead of "dogga dogga".  Lingo different, result the same.

[Antietam Classic Cycle]

As Charlie mentioned IF your pistons are reusable. Plus there is added cost of about $40 each way for shipping/packing/insuring because you need to package the stock cylinders like faberge eggs or deal with broken fins.

If you send to Millennium they will reuse your packaging to send the replated cylinders back to you the same way you packed them. So it got to be simply to replicate and sturdy. I ended up buying a sheet of 1" polyiso insulation cutting it on the table saw to make a box that fit the cylinder perfectly.  The I put into a bigger cardboard box and infilled it with more ply's of polyiso, bubble wrap and packing peanuts. Packaging alone cost me about $30.

That's odd - I've never received them back (8 sets done now) in the packaging I sent them in. Millennium has always used fresh new heavy boxes of the appropriate size plus a special made piece of cardboard slipped over the spigot of each cylinder. I save all of it and send the next set in those boxes. As Chuck says <shrug>.

[Perazzimx14]

That's odd - I've never received them back (8 sets done now) in the packaging I sent them in. Millennium has always used fresh new heavy boxes of the appropriate size plus a special made piece of cardboard slipped over the spigot of each cylinder. I save all of it and send the next set in those boxes. As Chuck says <shrug>.

Mine came back in the same packaging I sent them out just as I was told. 

[Two Checks]

Quote from: LesP on Today at 05:27:29 PM

As an afterthought, I was looking on eBay the other day and there was a 1976 850 T which looks very much like one that was for sale for some time on this site.
It looks to have popped up in Australia @ $12500 (US$8600)

Wasn't 1975 the last year for the T?