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"Slippage" when engine hot.

akhslo

New member
akhslo from San Luis Obispo, Cal.

1987 K-75 (my fourth K-75)

For about a year or so this bike, when hot, in first gear and sometimes 2nd, feels like a shaft is turning inside a gear and slipping for a second or two, then grabs and off we go
Have not had any of three mechanics able to identify the problem--had all apart and and could not find any noticeable problem with clutch or system parts. One thought it could be something tied to something in the clutch activation system, but could not find anything.

Any ideas out there?
Thanks,

Keith/akhslo
 
While it seems unlikely: the driveshaft is a 2 piece shaft bound with a rubber sleeve. I would expect it to continue to slip if the bond were broken, but it is easy to check.
 
When it "slips", is it smooth and the rpms rise? That might suggest oil on the clutch.

Or is it a few sharp clunky jerks? That might suggest very worn splines on the clutch disc or driveshaft.




:dance:dance:dance
 
Lee. How does the output shaft attach to the gear? And/or the crankshaft attach to the gear that engages the one on the output shaft? I haven't been in there for 25 years.
 
Paul,

The gear slides over the end of the output shaft and is held in place by the same nut that holds the clutch housing on top of the gear. Rotationally, there are two tabs on the front of the gear that mate with two slots on the rear of the output shaft.

The gear on the crank is cast as part of the crankshaft.



:dance:dance:dance
 
K-75 "slipage" when engine hot---slight rpm rise

Lee98--thanks for that tip--it is a slippage and not a jerk--in shop now to check it out again.
Just one more of those little things I hope that we will laugh about later for its simple solution!

Keith in SLO
 
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