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Clutch Adjustment

Additional thought: the disk goes in so the extended side of the hub points to the rear of the bike. I'm not sure it will even go in the other way on that bike, but if it did it would push forward on the spring I think.
 
Look at that assembly again. The spring is forward of the pressure plate. The pressure plate is forward of the disk. You put in a thicker clutch disk. That moved both the pressure plate and the center of the spring forward away from the back of the transmission. The clutch rod didn't get longer. So the adjusting bolt at the back of the transmission needs to be readjusted.

Thanks Paul. Yes, I considered the effects of the new, thicker clutch disc, but wasn't sure if a 0.9 mm increase in thickness could have that much effect on the clutch lever adjusting bolt (even considering the geometry of the clutch release lever). I was looking for some confirmation before I put everything back together and started screwing in the adjusting bolt.

The throwout bearing currently runs almost to the bottom of the bore when it engages the push rod (maybe 3-4 mm shy; did not measure). If that allows enough additional movement to release the clutch spring tension, then the bearing and rod will move backward as the clutch disc wears. Over time, the adjusting bolt will have to be adjusted out to compensate.

Start at the top. Adjust the knurled adjuster at the handlebar so there are 12mm of threads exposed between the adjuster and its locknut with the locknut against the perch.

Then go to the bottom. Loosen the 13mm lock nut and adjust the 10mm (head size) adjuster bolt so that there is 7mm free play between the lever and the perch.

Then try the clutch action.

Sounds like a plan. Once I get the clutch and transmission reinstalled I can adjust the clutch lever and cable free play before I put the rest of the bike back together (the adjusting bolt will be much easier to access) to make sure it is correct.
 
Additional thought: the disk goes in so the extended side of the hub points to the rear of the bike. I'm not sure it will even go in the other way on that bike, but if it did it would push forward on the spring I think.

Thanks. Yes, I got the clutch disc in correctly also (with the extended hub pointing toward the transmission). That's why I was puzzled by what was the problem.

Will reinstall everything once my new clutch bolt lock washers come in. On the plus side, the input shaft splines looked perfect, with residual lubrication and no apparent wear (still had machining marks on the top edge of the splines).
 
According to BMW the clutch disk changed in 1997 to a thinner disk. When changing the disk in an earlier RS the pressure plate must be replaced with the new one. The new one is thicker.

This may or may not be a contributing factor to what you are observing.
 
According to BMW the clutch disk changed in 1997 to a thinner disk. When changing the disk in an earlier RS the pressure plate must be replaced with the new one. The new one is thicker.

Thanks. There is a note on the realoem web page next to the clutch friction disc [SI 2100896(737)], but I did not check it. I'll do so at the dealer when I pick up some additional parts in the next day or so, and see if it says anything relevant to this.

However, the new disc I installed is thicker than the old one I took out (6.0 mm vs. 5.1 mm), so even if the new, new disc is thnner than the old, new disc (I could not find a spec for new thickness, only the wear limit), it is still thicker than the one I took out.
 
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