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Discussion Starter · #1 ·
Ok I finally got the flasher problem fixed, the muffler welded, and everything back together. Now something else went wrong already. I went for about a 50 mile ride yesterday, and discovered that after riding for a few miles, the clutch doesn't want to disengage. I can pull it all the way in while riding on the highway at around 60 mph, and nothing happens. It stays engaged. If I whack the throttle open a couple of times with it pulled in then it will release. It's only doing this after riding several miles. Just riding around town, stop and go, it works perfectly. It is properly adjusted. I didn't work on anything to do with the clutch. It's been fine for over a year. Since it works fine around town, I'm assuming the clutch itself is ok. I'm wondering if there might be a problem with the release mechanism. The only manual I have is a Clymer manual the guy I bought it from gave me. It looks like sort of a rack and pinion setup. I'm wondering if something could be sticking or worn. Or maybe something broke. But it seems strange that I can ride it around stop and go for over an hour with no problems. It only refuses to disengage after several miles riding with it engaged.
 

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What oil are you using? It’s possible the plates are sticking for some reason. Using the wrong oil can do this.
I’d suggest opening up the clutch cover and seeing if the outer plate is moving when you pull the lever (if the bikes on the side stand you won’t need to drain the oil)
If the plate moves, the interior clutch plates must be sticking, remove them and clean them, replace the oil with a motorcycle friendly oil and see if that solves the problem.
 

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Discussion Starter · #4 ·
I'm using just plain Castrol GTX 20w50, which is what I've been using since I got the bike. It's hot here in CA, over 100 degrees. This happened all of a sudden, after over a year of no problems. Does removing the cover require replacing the gasket? The gasket is $15 and shipping is another $10. It will likely work ok with the engine cold, as I am able to push the bike back and forth with the bike in gear and the clutch pulled in. It only seems to refuse to disengage after riding for a few miles without using the clutch.
 

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So, the plates are sticking when the oil gets hot. I’d first try switching to a 10w 40 and see if that helps. There might just be some burnt oil on the plates and it gets “sticky” when they are heated up. If the lighter oil doesn’t help you should disassemble the clutch and examine it. Look at the basket “ears” for notches as Spockster suggested.
One would think it would behave the opposite, the plates sticking when cold and not when hot. If the plates are in fact toasted, you’re better off replacing them instead of cleaning (and lightly sanding) them.
A new gasket will be needed, unless you manage to remove the old one without tearing it.
 

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Some things will stick due to expansion only after getting hot. You could see the same sticking in the rack and pinion inside the bevel gear case.

You can remove the round clutch cover and watch the clutch pack as you pull the lever. But if you need to go deeper you might have to pull the larger cover.

Check eBay for the gasket? They're usually better priced. Minor tears and clean breaks in the gasket can be sealed with sealer, but don't overdo it.



There's also the long pushrod that crosses from the bevel gear case to the clutch pack. But I would rule out other causes before going that deep. If the engine looks clean inside, the pushrod sticking is less likely.

Does pulling the lever feel normal when it's sticking, or does it feel notchy?
 

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Discussion Starter · #7 ·
Ok, I've come to some conclusions. Let me know if you think they are wrong. First, I removed both ends of the clutch cable and lubed it really good. It now works easier than it did. I made sure the slot on the arm that the bottom end of the clutch cable attaches to lined up with the mark on the engine, and that the bolt was tight. It still works perfectly riding around town, constantly using the clutch. It is smooth, and engagement is perfect. It is not slipping. And it got plenty hot. It's over 100 degrees here, the temperature gauge shows it is about as hot as it can get without overheating, which is normal, and the fan runs constantly. It's probably hotter in town than it is on the highway. Just to check, I purposely adjusted the clutch lever too tight, with no play, where it is right on the verge of slipping when fully released. Just slight pressure on the lever causes it to release. To me that means the release mechanism is ok. I then readjusted it properly. And since the clutch releases and engages smoothly, with no notchiness or inconsistency, that also seems to rule out wear or damage to the clutch basket and hub. It also does not make any noise. That only leaves the plates. I forgot to mention this, but this bike has always had an issue with the clutch sticking after sitting for a while, even just overnight, though it gets worse if left sitting for several days. I have had to either rock it back and forth in gear with the clutch in, or use the starter with it in gear with the clutch pulled in to break it loose. But once loose, it worked fine until it sat for a while. I had another bike that did the same thing, and it seems to be a fairly common issue on some bikes.

So to me, if the release mechanism is working perfectly, when the bike is hot, then it is ok. I don't see anything that could change by riding for a few miles on the highway. It's all mechanical, and should be something that either works or doesn't work. Same thing with wear or damage to the actual clutch basket and hub. That would cause improper operation all the time, not just after riding on the highway. So it would seem to be doing the same thing after being ridden a few miles on the highway that it has always done after sitting for a while. The plates are sticking together. They don't do it riding around town, because the clutch is constantly being engaged and disengaged, and they don't have time to stick. So I think the best thing to do is to inspect/replace the clutch plates, at least the friction plates. I don't have time to do it right now, will have to wait till Saturday. I'll take the clutch apart and inspect it. Has anyone used EBC or Vesrah clutch plates? They seem to have good reviews. And they are less than half the price of oem parts. Thanks for all the help.
 

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FREEBIRDS MC CENTRAL NY
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Ok, I've come to some conclusions. Let me know if you think they are wrong. First, I removed both ends of the clutch cable and lubed it really good. It now works easier than it did. I made sure the slot on the arm that the bottom end of the clutch cable attaches to lined up with the mark on the engine, and that the bolt was tight. It still works perfectly riding around town, constantly using the clutch. It is smooth, and engagement is perfect. It is not slipping. And it got plenty hot. It's over 100 degrees here, the temperature gauge shows it is about as hot as it can get without overheating, which is normal, and the fan runs constantly. It's probably hotter in town than it is on the highway. Just to check, I purposely adjusted the clutch lever too tight, with no play, where it is right on the verge of slipping when fully released. Just slight pressure on the lever causes it to release. To me that means the release mechanism is ok. I then readjusted it properly. And since the clutch releases and engages smoothly, with no notchiness or inconsistency, that also seems to rule out wear or damage to the clutch basket and hub. It also does not make any noise. That only leaves the plates. I forgot to mention this, but this bike has always had an issue with the clutch sticking after sitting for a while, even just overnight, though it gets worse if left sitting for several days. I have had to either rock it back and forth in gear with the clutch in, or use the starter with it in gear with the clutch pulled in to break it loose. But once loose, it worked fine until it sat for a while. I had another bike that did the same thing, and it seems to be a fairly common issue on some bikes.

So to me, if the release mechanism is working perfectly, when the bike is hot, then it is ok. I don't see anything that could change by riding for a few miles on the highway. It's all mechanical, and should be something that either works or doesn't work. Same thing with wear or damage to the actual clutch basket and hub. That would cause improper operation all the time, not just after riding on the highway. So it would seem to be doing the same thing after being ridden a few miles on the highway that it has always done after sitting for a while. The plates are sticking together. They don't do it riding around town, because the clutch is constantly being engaged and disengaged, and they don't have time to stick. So I think the best thing to do is to inspect/replace the clutch plates, at least the friction plates. I don't have time to do it right now, will have to wait till Saturday. I'll take the clutch apart and inspect it. Has anyone used EBC or Vesrah clutch plates? They seem to have good reviews. And they are less than half the price of oem parts. Thanks for all the help.
Yup. Sounds like plates. I'd do both friction and steel as you have it apart anyway and don't have to but gaskets again if the steel ones end up being bad. I've used EBC before and had good results.
 

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Discussion Starter · #12 ·
Wow. That actually looks like those notches were machined in there. I'm expecting (hoping) mine to be smooth, because of how smooth the clutch works, and has been working for over a year. If not the job is going to get a lot more expensive. That part is $420, and if it's bad, the hub is probably bad too, and it's $125. Plus all the plates, springs, gaskets, etc. I doubt the bike is worth it. I'm beginning to notice that quite a few parts for this bike are NLA.
 

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Wow. That actually looks like those notches were machined in there. I'm expecting (hoping) mine to be smooth, because of how smooth the clutch works, and has been working for over a year. If not the job is going to get a lot more expensive. That part is $420, and if it's bad, the hub is probably bad too, and it's $125. Plus all the plates, springs, gaskets, etc. I doubt the bike is worth it. I'm beginning to notice that quite a few parts for this bike are NLA.
That's why I always say that eBay is usually the best place to look for parts. The basket starts around $25, or $100 for everything in the clutch department.

There should be new clutch plates and steels there too.

The notches look machined because that's essentially what happens. Steel wearing on aluminum in a confined movement.
 

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Which ever brand you choose, I would recommend new springs as well. I used EBC and was/have been very happy. Honestly they may pretty much all be close in quality and I know I went with the most cost effective one at the time. If you have time you might look into the coffee grinder mod. Although I don't see many posts with issues related to it any more, as long as you are there, it does not take very long and if you have a drill and bits, why not? (Perhaps better oil is being used now and the issue does not occur as much now.) I am attaching a photo of my bike's basket and you can see the mod.

If you have never done a bike clutch before I cannot stress how important the torque is when going back together,enough. If you don't get it right you will have problems and spend a lot of time getting it right. I ended up getting a new torque wrench because mine was off and I did not want to take the time and have it re calibrated. Anyway, good luck.

Wheel Automotive tire Gear Rim Alloy wheel
 

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Discussion Starter · #16 ·
I have done a couple of dirt bike clutches. The reason for their failure was obvious. They were slipping because the plates were completely worn out. The housing and hubs looked fine. I have read a lot on here about that coffee grinder noise, but my bike has never had it. I have no idea whether the clutch has been apart before or not. Bike only has 21K miles on it. I was going to measure the free length of the springs, and keep them if they don't show any wear. I have put performance springs on a dirt bike, and they made the clutch noticeably harder to pull. Dirt bike clutches take a lot more abuse than street bike clutches. It seems that if the springs were weak, they would cause the clutch to slip instead of sticking. Something is wrong, what concerns me is it happened all at once. It seems like a problem with the clutch plates would have happened more slowly. Or maybe it has just now gotten bad enough to notice. When I take it apart, I will inspect and measure everything, but I will replace the plates anyway, with the hope that that solves the problem. I have never encountered it, but clutch plates can become warped, which is about the only thing I can think of that would cause sticking. I'll lay them on a piece of glass, and use a feeler gauge to see if there are any gaps. But if they are warped, it seems they would stick all the time, and the clutch would never completely disengage. I read everything in the manual about the clutch. It also mentions checking for heat damage and damage from lack of oil. The engine has never been low on oil since I've had it.
 

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I would replace the springs regardless. At close to being 20 years old they may be losing some of their tension and allowing slippage when you are on the highway without you really noticing it. I first noticed my clutch problems when I "felt" the rpms at 60 -70 mph seemed off a bit. Especially when I just rolled up the throttle without downshifting to get around traffic. When I pulled the plates out they were glazed. I sanded the metal plates on a pane of glass to clean then up as they were not warped Arround town I did not really notice much of an issue. However, slippage at highway speed would result in heat which could cause the plates to stick. That could account for your problem on long rides.

Measuring the height would only be part of the equation as they could be getting weaker and given how compact they are without measuring their compression rate their height may not be off much. (There are people out there that believe a spring will lose tension over time even if it is not being used. I have never really gotten into those discussions and just filed the idea away as one of those many things that I have heard of but cannot either agree with or dispute.)

You do not need to go with "racing" springs just oem type replacements. When I built a stroker motor with a high lift cam I always went with stiffer springs. Then I could shim as necessary to make the height correct and still be assured I won't be plagued by valve float at high rpm.

Also I make the round gasket(s), including the stator cover, myself from material I get at NAPA or Auto Zone. Harbor Freight has a decent set of hole punches for the bolt holes.
 

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Discussion Starter · #18 ·
OK, I took the clutch apart, visually nothing seemed wrong. The steel plates show no wear or warping. The dimples are clearly visible. The springs are well within limits, but I'll replace them anyway, since they are not expensive. No damage to the housing or hub. Completely smooth, no notches. The friction plates looked ok, but when I measured them they were actually slightly thicker than what the manual says. Like they were swollen. I would expect plates with 21,000 miles on them to actually be a little thinner, not thicker. I have no idea if they are oem or not. I ordered new Vesrah friction plates and springs. I decided to bite the bullet and ordered a new oem gasket from Partzilla. I don't want to get it back together and find an oil leak.
 

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Discussion Starter · #20 ·
Yes I did. The pressure plate moves in and out. Of course I was only able to do it with a cold engine, but I don't see any part of it that could change due to temperature. It's all mechanical with nothing that would work one minute and not work the next minute. Thinner oil might help, but I can't use it here. It was 110 degrees today and is supposed to be 112 degrees tomorrow. And it's been working fine for over a year with 20w50 oil. If the new friction plates and springs don't fix it, then I'll tear into the release mechanism.
 
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