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Strangest clutch issue I've ever seen but fixed in the end

Artie

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Today while replacing my slipping clutch I discovered

The Friction disc that has groove rather than block pattern that was for clutch rattle issues on K6 model completely disintegrated and left me with 5 friction discs and one extra steel plate I initially thought and this outside friction disc was as smooth as steel disc, I installed my new discs installed 6 frictions that came in package and works perfectly
This explains all the pieces that were in the oil pan during initial resto project this I posted about before because I couldn't figure out all these black gasket type material in oil pan never dawned on me that it was clutch plate material
At the time working thru carb,electrical issues slipping clutch on the list
It seems to all make sense now much better clutch feel too,bike has 30 K and after bunch of little things carb issues etc. is running sweet the original UJM at its finast!
Had me baffled
Anybody else ever see this????
 
Yeah, I've seen several disintegrated clutches. Some of which were caused by me.

Hope you flushed the oil system really good, especially the cam journals.
 
No I really dont recommend attempting to "flush" anything. If you try to force backwards all you are doing is pushing material into the main oil gallery, there is no way you can get stuff out of all the oil galleries with the engine together.You have to remove the engine to remove the valve cover anyway, then you have to take the cam and cam tower out to get to the oil gallery and the restrictors. The issue with the top end on the 750 is there is there is a oil restrictor under each cam tower. The jet hole is about the size of a needle and there has been issues with silicone breaking off and making its way in and plugging them. Gambling time....if the motor runs and you have verified oil getting to the top end then run it and hope the oil filter does its job. On the other side if some of the material gets into the oil gallery it will block the oil jet and you will seize the cam destroying it and the cam tower along with more than likely breaking the cam chain and thus bending valves. If it is all fairly large chunks and the screen on the oil pump caught it then you probably wont have an issue. The screen SHOULD have caught the big suff and the oil filter SHOULD catch all the small stuff.
 
Don't know the SOHC that well but like all other engines pretty much you will have to have all parts apart to shoot solvent through all holes to confirm fully open. You can have oil simply removing cam caps and still have a restriction from partial blockage that prevents 100% intended flow there. In short, no easy way past a certain limited amount of deduction there, the 'gambling time' he refers to.

I too have seen discs that shed lining, usually cheaper quality parts using lesser caliber adhesives that fail with heat. If you got high mileage screwy wear in the basket outer fingers where disc tabs engage; can do it too when some discs release repeatedly before others to load the leftover ones too much of the time. A worn basket will seem to work OK but then change up the discs by moving them around or substitute say a few of them to then not be exactly lined up with the wear and then the problem. You get some clutches working and some not.
 
Pull the cam adjuster caps on the valve cover on the intake side. With it running on the center stand not the side stand you will see oil on each side of the engine. You wont get much oil splash unless you rev it up. You cant see the actual cam bearings but if you have oil on each side of the engine then you know the oil restrictors are free and the chances are good that all 4 bearings are getting oil. The only way one bearing can get oil and not the other is if a passage in the cam tower is blocked, that doesn't happen often at all. Its normally one half of the engine meaning an oil gallery orifice restriction. If you get oil kicked up on all 4 intake valves you will be good. Ideally you would make a valve cover with a window in the whole top then you can watch everything...would be kind of neat to see it running too.:thumbsup:
 
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