I was having shifting problems with my '89 XT600, so I removed the clutch for routine maintenance, and when doing that I noticed that the clutch boss nut came off without a wrench. Other things were loose too, but not as bad, so I figured that this looseness was the reason for the shifting problems.

Anyway, as I'm reassembling it, I tighten the clutch boss nut to the torque specified in my manual, 51 ft lbs, and I notice that the clutch boss and the primary drive are bound, essentially rendering the clutch useless. Taking the clutch boss nut off cures the problem, so I finger-tighten the nut. If I tighten it so that it doesn't spin freely (about 2ft lbs), the clutch boss spins freely. If I tighten it as tight as I can with my fingers (maybe 3-4 ft lbs, I don't know), it binds up. It will still spin if I really grab onto it, but there's very noticeable resistance.

Is there something wrong with the clutch, or might something be out of spec? If so, what could it be? Or should I just give up and finger-tighten the clutch boss nut and count on the lock washer tabs to hold it in place?

Any help is appreciated, thanks.

There is supposed to be a washer (approx. 2 mm thickness, with splines on the inside) between the two clutch parts. Are you sure this is installed - if not this would explain the problem.
Normally, the clutch nut should be tightened, 70 Nm as I remember.

So, what your bike has is not what it should be.

If you like, can send you exploded view of the clutch showing the parts. PM me.

Auke

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Auke
http://aukemarieke.blogspot.com

Ditto, and it's a right miserable b"£$ER% to loosen or tighten too. I broke a basket when the torque wrench slipped off £$%^&*!

Use a airgun to take that nut on and off...I broke to studs trying to take the nut out and had to buy a new part(the one that has the holes for the clutch springs)

As said, there should be a washer between both clutch hub and boss... it is about 3mm thick..

When I toke my clutch apart to put the the idle gear for the kickstart I forgot to put that washer back in between both clutch parts and it was happening the same thing that's happening to you...

Oh and get the other washer that helps the nut not vibrate loose!very important!

Vando

To block the clutch to do / undo the nut ....

1. Put in 2nd gear
2. Fix tie-down strap, the sturdy type, around the wheel with tyre, two or three times around does it. Other end goes to a sturdy point on the frame (footrest or whatever)
3. Get out your wrench and undo / do the nut

Obviously, only works with the engine in the frame and the chain installed ... :-)

Auke

__________________
Auke
http://aukemarieke.blogspot.com

I have a tool specifically for holding the clutch boss, it looks like a Vice-Grip with big L-shaped jaws. It works pretty well. I broke one of the studs off of my original clutch boss, thinking I could get by without the tool. So I bought a new clutch boss, and the appropriate tool to put it on.

The washer that goes in between the two pieces is there, although it seems to be stuck in place and I can't get it off. It does not rotate indepentently of the primary gear, and seems to be what the clutch boss is tightening against when I tighten the nut. All the parts appear to be normal, but I can't torque them properly.

I have a new (well, once used) lock washer for the nut, but I'd like to know why I can't tighten the clutch nut as much as I'm supposed to.

Thanks for all the help so far guys!