Me thinks I may have a problem

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Take your sump plug out and check that the circlip on the sump filter body is intact, it may have been damaged if you "made" your smaller drain plug for the sump body. Easy enough to check before a teardown .
the circlip for the sump plug is intact. the sump plug screen was actually pretty debris free but the smaller plug (with the magnet end) that fits inside the sump plug captured a bunch of the metallic bits, as did the magnetic crankcase drain plug
 
well, i was able to remove the head this evening after messing around long enough with the rods,,,,i havent removed the barrels yet,that hopefully will be tomorrow, ,,,,but I'm leaning towards the idea earlier Me thinks I may have a problem Me thinks I may have a problem Me thinks I may have a problem Me thinks I may have a problem Me thinks I may have a problem presented that the piston pin circlip (or circlips) failed. (by seeing the marks on the cylinder walls,,,both sides of the right hand cylinder) but what surprised me was the amount of coke on the top of the pistons
 
Sometimes it’s difficult to tell cause from effect...

Those scores in the cylinder would lead to oil being burned which leads to the coke build up.

But the bores look more scored than just the pins / clip area, so...

Maybe you’re running rich, which causes the coke, but also causes petrol wash which causes the scoring...
 
Sometimes it’s difficult to tell cause from effect...

Those scores in the cylinder would lead to oil being burned which leads to the coke build up.

But the bores look more scored than just the pins / clip area, so...

Maybe you’re running rich, which causes the coke, but also causes petrol wash which causes the scoring...
yup, good points, tomorrow after the barrels come off I'll get some more pictures,,,then the process begins on deciding what I will need to do to fix this all up,,,glad it's not summertime in The Black Hills,,,hopefully it'll be all put back together before next spring,
 
It does look as if both clips came loose?
it does, doesn't it,,i'll see more tomorrow, but seeing a partially round gouge on opposite sides of the cylinder wall sure makes me think the pin was moving back and forth in both directions,,,(inboard and outboard)
 
One of the Buells I own came from the factory with only 1 clip in each piston, the guy I purchased it from said he had put quite a few miles on it before he noticed any smoke. It was still under warranty and the dealer was honest enough to tell him what it was.
 
It does look like there was wrist pin movement, is this still a standard size bore ? In 1988 I went 0.020 over on mine,still running fine. Seems like a lot of buildup for 2000 miles, maybe it wasn't cleaned up real good when rebuilt or just been running rich. Keep us posted with your progress :)
 
I removed the barrel this morning and the right hand piston inboard pin circlip was gone, but, strangely, the outboard circlip was still in tact and in place. from the looks of the cylinder wall (both inboard and outboard)Me thinks I may have a problem Me thinks I may have a problem Me thinks I may have a problem Me thinks I may have a problem Me thinks I may have a problem Me thinks I may have a problem Me thinks I may have a problem I would have bet that both circlips would have been gone.
 
Fugly! I feel your pain! Hope it sorts out in time for your Spring season. I'm pulling for you!
 
When the wrist pin came apart and began chewing on the cylinder/piston, the resulting spooge was encouraged to travel through the pin and feast on the bore next door.
 
It does look like there was wrist pin movement, is this still a standard size bore ? In 1988 I went 0.020 over on mine,still running fine. Seems like a lot of buildup for 2000 miles, maybe it wasn't cleaned up real good when rebuilt or just been running rich. Keep us posted with your progress :)
as best I can tell from reviewing the work history/documentation i received with the bike the cylinders were "re-honed",,,that was about the extent of the description of cylinder work done. so, not really sure if it's a standard bore or not, yet.
 
IMHO there is more going on here than the circlip breaking. It looks like there are signs of detonation in the timing side cylinder with erosion from the top to the pin boss. It appears this led to piston seizure and possibly that is what caused the circlip to come loose. What does the pin and bottom of that piston look like. Any indication of abnormal heat like a blue or straw color. It also looks like there are aluminum specks on the top of the piston and combustion chamber. Something about the combustion wasn't right in that cylinder as evidenced by the excess build up. Maybe a badly leaking intake valve seal. It would help if you would lable each picture as to which side you are looking at. Oversize pistons are almost always stamped that way on the top, so no stamping probably means std.
If you don't ferret out what caused this problem you could be facing it again after a rebuild.
 
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To me your last picture look like the piston has seized.

If so, that’s a separate problem to your lost circling.

The damage could easily have caused the oil burning that resulted in the coke build, or, as mentioned before, you motor could be running badly rich, with the resulting seizure being a result of petrol wash.

So, you obviously need new pistons and bores. And you need to look closely at carburation.

What does the bottom end look like? Has the shrapnel damaged anything? Are you gonna strip the bottom end, or flush it and leave it?
 
disassemble - inspect - repair - reassemble

Good work, You're half way home. It could have been much worse. At least you didn't snap a connecting rod and put it through the crankcase. As much as the damage is really just bore/piston related, I would tear the whole thing apart and clean everything well before reassembling. If any pieces of metal are in the main bearings, crankshaft, oil pump, or big end shells, then your quick rebuild will be failing and coming back apart in short order... For all you know the big end shells are scored too judging from the looks of the piston... You can do it. Take your time. In the spring, it will be back together pulling like a freight train doing 100mph up hill. You'll be confident that it's all new and solid as a rock for years to come.

... and the bad news is those circlips are not soft metal like aluminum, so you could be replacing a lot of stuff, like the cam, the oil pump, lifters, and anything else that suspended metal particles in the oil can destroy. You'll be inspecting a lot of stuff and making a lot of judgement calls on what is good and what is "toast". That can be expensive and stressful. Patience is manditory, and asking this group questions when you're in doubt is a blessing. I might call Jim comstock and ask if he would inspect and repair your barrels. I'd send him the head too. Then you know you're getting the best advice and the proper machine work to go forward.
 
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IMHO there is more going on here than the circlip breaking. It looks like there are signs of detonation in the timing side cylinder with erosion from the top to the pin boss. It appears this led to piston seizure and possibly that is what caused the circlip to come loose. What does the pin and bottom of that piston look like. Any indication of abnormal heat like a blue or straw color. It also looks like there are aluminum specks on the top of the piston and combustion chamber. Something about the combustion wasn't right in that cylinder as evidenced by the excess build up. Maybe a badly leaking intake valve seal. It would help if you would lable each picture as to which side you are looking at. Oversize pistons are almost always stamped that way on the top, so no stamping probably means std.
If you don't ferret out what caused this problem you could be facing it again after a rebuild.
roger that,,,i'll be doing more disassembly to get as much info as i can,,and annotating the pictures. the piston top is stamped .020. inside the piston the nomenclature is N1777. the pin looks fine there isnt any indication of a blueish or straw coloring to the piston. I'll get some more pictures and annotate them properly.
 
disassemble - inspect - repair - reassemble

Good work, You're half way home. It could have been much worse. At least you didn't snap a connecting rod and put it through the crankcase. As much as the damage is really just bore/piston related, I would tear the whole thing apart and clean everything well before reassembling. If any pieces of metal are in the main bearings, crankshaft, oil pump, or big end shells, then your quick rebuild will be failing and coming back apart in short order... For all you know the big end shells are scored too judging from the looks of the piston... You can do it. Take your time. In the spring, it will be back together pulling like a freight train doing 100mph up hill. You'll be confident that it's all new and solid as a rock for years to come.

... and the bad news is those circlips are not soft metal like aluminum, so you could be replacing a lot of stuff, like the cam, the oil pump, lifters, and anything else that suspended metal particles in the oil can destroy. You'll be inspecting a lot of stuff and making a lot of judgement calls on what is good and what is "toast". That can be expensive and stressful. Patience is manditory, and asking this group questions when you're in doubt is a blessing. I might call Jim comstock and ask if he would inspect and repair your barrels. I'd send him the head too. Then you know you're getting the best advice and the proper machine work to go forward.
thank you for the inspiration, much appreciated,,much more to come I'm sure. i agree, it could have been much worse.. I'm very glad I was only a few blocks from home when the engine stated to exhibit it's "misfire" symptoms.
 
Drain your oil tank and shine a lite inside look for metal glitter at the bottom, (theres a little oil that won't drain). if you've got glitter here go with o0norton0o suggestion and crack it open to clean....
 
Schilling,
really sorry to see this. Looking at the pics you posted I fail to see how the circlip ended up in the sump. The piston doesn't look sufficiently damaged below the gudgeon (wrist) pin to have allowed a circlip past it. How deep is the groove in the bore? It's my suspicion that on reassembly after the honing work the circlip fell into the case where it eventually got beaten up by the crank, and for whatever reason a clip was never fitted to that side of the piston. (Anyway that's conjecture). The pin will then float and do it's worst, and as Dutch said the swarf will run along the centre of the pin and eat away at the other side and the more is wears the further it will travel.

You've probably realized that your head gasket was leaking (pretty badly I'd say) However in this case I think it saved your bacon as the extra lube being sucked into that bore stopped it from seizing completely.

Your initial photo also showed what look like bronze flakes on the tissue. Were they from this engine? If so I would not waste any more time, just start pulling the bottom end apart as well.

Cheers,

cliffa.
 
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