Clutch question…

[viclioce]

I have a clutch in the Super Rat. Relatively new clutch plates. I started with 3, .05 spacers and if I released the lever the bike would jerk and stop. I added a 4th .05 spacer & when I released the lever the clutch felt like it wasn’t fully engaging. I loosened the cable and no change. What am I missing? Driver comes for it tomorrow. I need to get it tuned in so it engages properly. Victor

[Bullfrog]

Sounds like the teeth of the steel plates may still have sharp edges. If so, the "burr" can (will) catch (dig into) the softer aluminum of the clutch cage. As the clutch is released, the steel plates hang up till the pressure builds and the plates pop free from the hang up - and presto-chango, you go from full disengagement to full engagement in a snap (which often kills the engine). There is an article on blue printing the clutch in a long past issue of the Resonator Revisited. Teeth of the clutch cage need to be smooth. The previously mentioned burr can gouge a "washboard" surface on each of the cage teeth.

Ed
PS: You select the number/thickness of the shim stack based on clutch lever freeplay (the lever on the engine). If you have no freeplay, the clutch will not be allowed to fully engage.

[viclioce]

Yes. I understand the free play setting. As I’ve told you before, I always mark the 3/32” gap for free play on the outer case. Thought I had it with 3, .05 spacers. It seems like .05mm is a lot thinner than 3/32”. Can’t imagine why 1 additional spacer would go from not feathering to a full slip of the clutch. I will have to pull the clutch back apart in the cold, cold morning…… Victor

[viclioce]

I have a nice set of small files I bought for blueprint filing. But, I must admit I failed to do it this time…. Victor

[Bullfrog]

As you have discovered, a half mm shim has a larger effect on freeplay than you might expect - that's because of "leverage ratios". The contact point of clutch lever cam on the inside of the case is very close to the center-line of the clutch lever shaft, while the end of the lever on the outside of the case is a lot farther away from the center-line of the shaft. So "moving" the contact point by .5mm results in (say) ten times as much change out at the end of the lever on the outside.

It is possible (but not likely) that the clutch cage teeth aren't wash-boarded -- I'll cross my fingers for you on that. But be sure to get rid of the sharp edges on the steel plates. Those burrs will "re-washboard" a cage in no time.
Ed

[viclioce]

Will do. I wouldn’t have thought to do the edges of the teeth on the steel plates. Thanks for that tip. I plant to get out there this morning and lay her in her left side and pull the clutch assembly. I’ll report back what I found, later this afternoon. Thanks for the pointers. But it’s gonna be cold!!! . Victor

[Bullfrog]

There are detailed diagrams of the factory burr on the OEM steel plates in the clutch blueprinting article.
Ed

[taber hodaka]

I think those plates are high strength a small file may not work so well, a small drimel with stone might go better. ------- Clarence

[matt glascock]

Hey, now you're...tal......kin'.......... Yes Captain...

[viclioce]

Got it all done! Bike was packed up at 1:40 and left by 2:00! Thanks again!!! Victor

[Bullfrog]

Uh-oh. Everyone take a step back, Matt is grabbing his Drexel. No one is safe now. Clarence, you may not know the dangers you have un leashed!
Ed
PS: I prefer a small fine file for smoothing the burrs on the teeth of the steel clutch plates. (I just can't get non-wavy edges with the Dremel.)

[Bullfrog]

DAGNABIT! Dremel!!!! (That's what I typed!)
Ed

[matt glascock]