ALTO 8 Plate Clutch Mod XS650SK


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Coldwater, Mississippi
I was suffering a slipping clutch. I swapped out plates with a spare engine I have and the clutch was still slipping. So....
I acquired an Alto eight plate clutch conversion from @gggGary. (Thanks Gary!) He also provided me with a new steel plate.
My 1983 XS650SK has a six plate clutch. This is the case with 1980 to 1983(1984) XS650s. So, I decided to try a seven plate conversion rather than swap the entire clutch assembly.
I loosened the clutch cable and the clutch adjustment on the left engine cover and I drained the engine oil. I removed right side engine cover and then the six spring loaded bolts that hold the clutch together. I replaced all of the friction plates with the Alto plates plus one and the additional steel. I should add here that I worked the steel plates with 100 garnet paper to break the glaze.
After reassembly I added 2.5 qts of Lucas full synthetic motorcycle oil JASO MA-2. It sat like that for a couple of days and I occasionally pushed the kicker down a few times with the clutch handle squeezed to wet the clutch. After a few days, I adjusted the clutch and cable and rode it. I gave it a good hard run.

IT'S FIXED! NO MORE SLIPPING. I have a seven plate conversion.
:bow:Marty was the pioneer on this. :bow2:
@5twins had done the math and said it would work. So we believed him and tried it.
Success. Well at first blush anyways. If I know Marty (and I do) he'll wring it out and let us know how it goes over time/miles.

Was out on Madness tonight after it sat for a week or so, it left the ranch with no issues or judder even on first release of the day.
Is the dampened hub a nice improvement over the regular clutch? I don't expect Yamaha made a change like this for no reason.
I feel it is. The 650 doesn't have a cush drive in the rear hub, the sprocket is solid mounted. Instead there are 6 little coil springs on the back of the clutch basket to absorb drive line snatch. Over time and with lots of use (and/or abuse), these springs can start breaking. So, anything to ease the strain on them is a good thing and the dampened inner hub does that.
5twins seems to say the 6 spring as used in all the XS clutches is a good thing not specifically the the late 6 plate change.
It seems like I have run into more of the late 6 plate clutches that slip compared to the earlier 7 plate. Then again I tend to find more of the later specials hiding in barns n sheds.....
I'm going to use the Alto plates so I'll be able to fit 7 in there. I'm going to try one last time to get the electric start to work while I'm in there but If I can't get it I'm going to rip that junk out for a bit more oil capacity.