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1990 YZ 125 Clutch Issues?

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So, I got this YZ from a buddy last month. He gave it to me with a clutch that doesn't work. When I first looked at it, the clutch cable was siezed up, so I bought a new one. Threw the new cable on, put the bike in gear, pulled the lever, and rocked it back and forth about, and nothing would happen. The clutch was locked up completely. I pulled it apart, and was looking at it, and decided to just pull the whole thing. I cleaned it up a bit, and put it back together, and the clutch still wouldn't disengage. I've taken it apart, and put it back together about 10 times lmao. I just cant find the issue. I checked all the adjustments, made sure the actuator arm was set correctly, but nothing worked. Now, my new issue. I pulled off the side cover, pulled the clutch plates, inner hub, basket, everything. Cleaned it all up, made sure all was well, and then put it back together according to the manual and microfiche. Now, the clutch won't engage. Its always disengaged. When it is in gear, i can hold the inner hub with my hand, and spin the sprocket, and the basket will spin, but not the inner hub. 

 

Hopefully you're understanding how I'm trying to explain this. Seems like depending on the bikes mood, the clutch will either be stuck engaged all the time, or be stuck disengaged all the time. I have no clue what the hell is going on here lmao. I was thinking maybe it could be the plates, but then it wouldnt be stuck being engaged all the time would it? I'm completely lost here. It's definitely all put back together right. I've double checked it, triple checked it, checked it about 15 times actually lmao. This is my first bike, and the first wet clutch I've worked on. I'm fairly mechanically inclined, and I know what I'm doing, but I have no clue what to think about this lmao.

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you need to check everything is where it should be.

 

start with the actuator arm and work over to the actual clutch,something has to be out of place or worn.

 

also what is the condition of the basket? is it notched?

Edited by Excitable

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I'm not sure on your current problem of being stuck dis-engaged, but I can tell you the '89-90 bikes are infamous for having dragging/non-disengagaing clutches (the original symptom you described).

 

Unfortunately the side cover is many times the culprit - the bore of the lifting rod gets elongated and the stack will not pull apart evenly.  Back in the day, we'd replace the side cover when we replaced the plates (every half-dozen races or so).  Now the bad news - the side covers are no longer available from Yamaha.  Same with the inner hub.  I had an '89 that i dumped a bunch of money into restoring recently and gave up after having so many clutch an ignition problems.  

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you need to check everything is where it should be.

 

start with the actuator arm and work over to the actual clutch,something has to be out of place or worn.

 

also what is the condition of the basket? is it notched?

I pulled the whole thing apart about 9 or 10 times just to check it with the microfiche and diagram to make sure everything was put back together right. Everything seems to be good, so I dont think thats the issue. What all should I look for with the actuator arm? If you're talking about adjustments, I made sure it fell between the marks on the case when it was set up. The arm should fall between the two lines when its engaged, right? or should it come into the marks when you pull the lever? As far as the basket and the inner hub, theres minimal notching, and by that, I mean you can see that theres some marks, but you can't feel them. I'm pretty sure it's not that either. I ordered new plates last night, so hopefully that helps.

 

I'm not sure on your current problem of being stuck dis-engaged, but I can tell you the '89-90 bikes are infamous for having dragging/non-disengagaing clutches (the original symptom you described).

 

Unfortunately the side cover is many times the culprit - the bore of the lifting rod gets elongated and the stack will not pull apart evenly.  Back in the day, we'd replace the side cover when we replaced the plates (every half-dozen races or so).  Now the bad news - the side covers are no longer available from Yamaha.  Same with the inner hub.  I had an '89 that i dumped a bunch of money into restoring recently and gave up after having so many clutch an ignition problems.  

Well, that's a bit of a downer, lmao. I put it back together one last time last night before I ordered new plates, just to be sure I wasn't wasting money on a new clutch, and low and behold, the damn thing went from being stuck disengaged all the time, to now being engaged all the time. I'm hoping new plates and oil will help here. I ordered new frictions, steels, and springs last night, and some Bel Ray Gear Saver 75w. I'm not sure what the previous owner had in it. I'm thinking it was 10w-30 or 10w-40. It seemed pretty thick, but I'm no fluid expert. When I opened the clutch up for the first time, some oil came out, but not too much. Maybe the previous owner didn't put enough oil in it, and messed it up? I know when he gave it to me, the clutch cable was seized up, so he was riding it without the clutch, and pop starting it. So I'm hoping theres no transmission issues along with it either. So if plates don't fix it, I can either A) Get rid of it B) Try to find a new side case. or C) Look for a new push rod? & by side case, do you mean the clutch cover, where the actuator arm slides in? Ahhhh, I'm just ready to get my insurance money so I can go buy a brand new bike lmao.

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Looks like new clutch plates might have fixed the issue. Also might have been something to do with the springs, because the ones I got in the kit are quite larger than the ones that were in the bike before. Finally got the carb and everything dialed in, and it looks like the bike is good to go. Thanks guys!

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