Why is my DR650 clutch locked up?

As some of you may know, I'm trying to recommission a 1990 kick start DR650. Well after struggling to get it running, without breaking my leg, I've now got a problem with the clutch. It runs fine, but the clutch will not disengage, so as soon as you drop it into gear, it tries to spin the back wheel and stalls. When I had it apart to repair the kick start mechanism, I noticed the fingers on the clutch "pressure disc" had been glued together after some previous damage, so I got a spare engine and replaced the whole clutch unit after getting it running and having this problem. Today I pulled it apart again, and cant see anything wrong- there's the right number of friction and intermediate plates & they're arranged correctly.

With the clutch basket off, you can turn the rear wheel (with it in gear) and it doesnt move the piston. With the basket bolted on, but no friction plates, it's still free. As soon as the friction plates are fitted and the centre nut is tightened (the picture below is this stage) it locks up. If I slacken the centre nut slightly, all is loose again. Anyone got any ideas what I'm not seeing?

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I don't know.

there sure are a lot of clutch not working threads lately & they all seem to have the same problem.

good luck! :busted:

Looking at the parts fiche it looks like you have it assembled wrong. It shows the nut holding the "pressure disk" and "primary driven gear" to the shaft. Then every thing else goes on after. You have the "sleeve hub" on as well before you put the nut on, clamping it all together solid. This is just a guess by looking at the parts fiche. I have never worked on this model.

Looking at the parts fiche it looks like you have it assembled wrong. It shows the nut holding the "pressure disk" and "primary driven gear" to the shaft. Then every thing else goes on after. You have the "sleeve hub" on as well before you put the nut on, clamping it all together solid. This is just a guess by looking at the parts fiche. I have never worked on this model.

I understand what you're saying, and from the 'fiche, it does look like I've got it wrong. From memory (its too cold & late to go back into the garage!) I'm pretty sure it cannot go any other way, but I'll try to have another look tomorrow.

As a side note, I tried bolting in together as it is in the photo, but without the plates & it was nice and free. But it does seem to lock up as the centre nut is tightened, making me think something is not right and its clamping itself together.

I'll keep you updated, I just hope I get time to get on it tomorrow...

The four springs are what locks the clutch together. So it should be free until you install the springs, "release plate" and four bolts. So something is definitely wrong there.

Now that I look at it again though, it would seem the nut would probably hold the "sleeve hub" to the transmission shaft. The fiche doesn't show it that way though. The "pressure disk" should float in behind all the clutch plates until you install the spring assembly. It just seems like you have too many plates in there or something.

The four springs are what locks the clutch together. So it should be free until you install the springs, "release plate" and four bolts. So something is definitely wrong there.

Thats what I'd expect, so I left it off, thinking the plates cannot lock up without it- they do though!

Now that I look at it again though, it would seem the nut would probably hold the "sleeve hub" to the transmission shaft. The fiche doesn't show it that way though. The "pressure disk" should float in behind all the clutch plates until you install the spring assembly. It just seems like you have too many plates in there or something.

There's the right amount of plates, and the pressure disc is still floating.

One other thing that has occurred to me is maybe the plates are contaminated with the wrong (too thick) oil and in this cold weather, it is causing too much stiction? Although I had the bike running for about 10 mins last month, and the clutch still wouldnt disengage, so I guess not.

So in that picture if you grab the four nubs of the pressure disk it is still loose and floating? If so, then the plates just have to be stuck together. I have had that problem before with aftermarket performance plates. When it's cold or you haven't rode it for a few weeks they don't want to separate. Just stomp it into gear and get it moving and ride it around with the clutch lever pulled in. It will eventually let loose. One other thing I thought of is the release setup. There is a rack with teeth and the shaft has teeth, release bearing. If some of that is out of tolerance, it might not have enough movement to actually release the plates.

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So as the nut is tightened down onto the clutch sleve hub #5 it locks.

This would mean that the hub #5 is sandwitching the plates together onto the pressure plate #11.

Which would make me think that the spacer #13 isnt long eneough or the washers are to thick between 11 and 12, or 12 and the engine which would make the spacer shorter.

There were a few different types of bikes in that 90-95 year range, e start and kick, not sure if there is any difference between the 2 and if you have the right parts. If you still have the old cage check it is the same.

Also check that if you are using a mix of old and new plates that they arnt worped on a sheet of glass.

Check the total stack height.

As said before, once the nut is tightened up to spec in your photo, the clutch pressure plate #11 should rattle around if you grab the fingers of the pressure plate and wiggle. If it dosnt thats the problem.

Good luck. PS thats a clean looking machine.

I could also be that the washer between #11 and 12 has too large an OD and dosnt fit through the pressure plate, forcing the pressure plate out. Not sure if the 2 washers have the same OD and could be switched about.

If all else fails get a marker, clean all the surfaces, colour in all the mateing faces and all surfaces on 5, 11, 12, 13 and the washers, you dont have to entirly colour in but put lines from inner to outer in several places both sides. Start tightening and turn it over at the same time untill it locks, disassemble and look for whats been touching.

Looking at the parts fiche it looks like you have it assembled wrong. It shows the nut holding the "pressure disk" and "primary driven gear" to the shaft. Then every thing else goes on after. You have the "sleeve hub" on as well before you put the nut on, clamping it all together solid. This is just a guess by looking at the parts fiche. I have never worked on this model.

I concur, the outer "basket" should be held tight by spring pessure only, sit there and work out how it works, step-by-step.

I don't know about the 96+ DR's but the pre96 have an inverted clutch

I believe we are having the same problem.

I have a 92 dr650 that I put the ebc kit in because my clutch was slipping a little in high gear. Now I cant get the clutch to disengage. I’ve had the whole thing apart 4 times, measured every fiber/plate and spring, torque to spec of the pdf manual I have and still nothing is working.

I just came back in the house from putting back in the original clutch fiber/plate and springs that I knew worked but slipped. Here is the kicker, it still will not disengage! Mechanically I think we are doing something wrong, we are over tightening something, what? I have no ideal.

I’ll keep you posted and if you find anything out please let us know. I sure there is others out there with the same problem.

So in that picture if you grab the four nubs of the pressure disk it is still loose and floating?

Yes, the pressure disc is still loose & floating- that was my first thought too.

If so, then the plates just have to be stuck together. I have had that problem before with aftermarket performance plates. When it's cold or you haven't rode it for a few weeks they don't want to separate. Just stomp it into gear and get it moving and ride it around with the clutch lever pulled in. It will eventually let loose.

The plates do feel tight together, like the oil is sticking them, but they do seperate if I try to move them with my thumbnail, but I think this may be my next option. Before I reassemble it, I'm going to soak the plates in fresh oil as I dont know what sort of oil was in the engine previously.

One other thing I thought of is the release setup. There is a rack with teeth and the shaft has teeth, release bearing. If some of that is out of tolerance, it might not have enough movement to actually release the plates.

I've even tried winding the adjusters right out, so (in theory!) the clutch should be disengaged even before I pull the lever.

There were a few different types of bikes in that 90-95 year range, e start and kick, not sure if there is any difference between the 2 and if you have the right parts.

Check the total stack height.

The second hand clutch I'm using definitely came from a kickstart engine, although I've never seen it running, the guy I bought it from seemed genuine, so I've no reason to think its not the right clutch. It looks the same as my old one too (but I'd not seen mine running either!)

Do you know what the correct stack height is?

Good luck. PS thats a clean looking machine.

Thats the weird thing, the bike looks like its had a lot of money spent on it over the years, in fact I've got receipts for more than £1500 in parts, so I'm really surprised that there's a problem like this with it!

The only other thing I can think of are the washers, one behind the basket (13 in the diagram above) and the one between the basket (12) and the pressure plate/sleeve hub (11&5) These both look like they've worn, could they become too thin and maybe that will lock it up?

The only other thing I can think of are the washers, one behind the basket (13 in the diagram above) and the one between the basket (12) and the pressure plate/sleeve hub (11&5) These both look like they've worn, could they become too thin and maybe that will lock it up?

Nothing should tighten on the washers, thats what the spacer is for, the main nut tightens the sleeve hub onto the spacer #13. The washers would only cause a problem if they were too thick.

As for the stack height, I cant find a total, but add this up with a calculator for the fiber plates.

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So you say that the pressure plate #11 is loose and rattles around when the main nut is tightened. Which would mean that the sleeve hub #5 would be binding onto the gear assembly #12 .make sure that the gear assembly is fully seated, usually it takes a bit of fiddling to get the teeth to line up on the outer and inner sprockets.

I think I've found the problem...

After looking again at the clutch, I tried swapping individual components, untill something changed- luckily I've got a spare engine! It looks to me like the 2 spacer type washers, and the basket centre spacer (number 13 in the diagram) have worn, causing the basket to bind when the nut is tightened. After swopping these from the other engine, it no longer locks up. They're still worn, just not as bad, so I'm going to order new ones just to be safe.

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I think you’re on to something.

I was just sitting here thinking about what I was doing different from when I pull the clutch off the first time. (Clutch sleeve hub nut)

What did your clutch sleeve hub nut look like when you first took it off? Mine was only finger tight and there was no way that it was torque too the 29.0- 43.0 lb-ft that the manual calls out. I thought that the nut had just backed out over time, but that can’t happen with the lock washer on. Maybe when the thrust washers wore down it caused the nut to loosen that way. Then when we go to torque the nut back to spec we’re actually pulling the basket farther in and causing it to bind.

I’m going to order new washers but for the time being I’m going to try backing the nut torque down to 10-15 lb-ft. When I get the new washers I’ll try manual spec again and see what happens.

I’ll let you know how it works out.

I bought the bike with the clutch basket in a box! The kickstart mechanism had failed on the previous owner, causing the kick lever to smash the crankcase cover, so the he had taken it apart to try and see the problem, but gave up.

I got it all back together this afternoon and the clutch is still binding. If I slam it into 2nd, the engine seems to turn a few rotations before locking up, so something is still rubbing. The thrust washers and spacer I fitted from my other engine were also pretty worn, so when my new ones arrive, I'll have another go- I cant see it being anything else, fingers crossed!

How are you making out with you clutch?

The 2 thrust washers and bush for the basket arrived earlier this week, but as yet, I havent had a chance to put it back together. I'm hoping to get on it tomorow.

I'll keep you all updated as soon as its back together...

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