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Weird clutch issue

1203 Views 34 Replies 7 Participants Last post by  JunkyardDog
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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It's definitely weird, I'm having trouble coming up with a problem that would happen this way. It hasn't been sitting around, it's had the same oil, and this just began. But it works ok when it's cold, right?

About the only other thing is possibly the rack and pinion is sticking after it warms up.
Can't rule out the pushrod sticking yet.

Edit... But you said the hand lever pulls normally when it's sticking.

I have seen the rack broken, but don't really see a connection with the heat.
When I swapped out the clutch kit, the manual stated to put Moly on the pushrod before reassembling. If it is a part that needs to be lubed then it’s a definitely something that can stick I would assume.
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If you can get the center nut off the basket, you should be able to pull the pushrod out that side and see if it shows signs of sticking, clean it up if there's varnish built up.

It's just a straight rod, so should come out either side.

With an impact gun, you can hold the basket with a gloved hand to spin the nut off.

Another method to hold the basket without buying the tool... A penny between the gear teeth, or just stuff a rag in the gears. Totally harmless.
That nut is 98 ft.lbs. I'll see what I can do with it. I don't have a helper, so the holding tools with a handle wouldn't do me any good. Stuffing something in the gears seems like a better idea. It's going to be a while before the new parts come in, so I have time to mess with it a bit.
I have the EBC Clutch tool and all things considered it is faster to use my dead blow hammer, 18 inch breaker bar and a penney between the gears. When my son and I split his case we went through about 6 cents tearing it down and going back together. The tool is a little too narrow, thin and the handle is shorter than I would prefer. I have only used it once

If you have a impact wrench it is easiest but I don't always use one. Sometimes to many tools, sockets, wrenches and an air hose make for a cluttered work space. Since I trip over my own shadow unless I am in a hurry I leave most of my air tools on the wall. Although there are times the only way to break a nut loose is with a good impact wrench a wrench without enough torque is just about worthless.
I have the clutch plate and springs. I'm still waiting for the gasket to come from partzilla. I decided not to remove the nut. It would require removing the whole right side engine cover, along with a lot of other parts, and more gaskets. I'm going to put it back together with the new plates and springs, and if it still does the same thing, I'll look into taking it apart further. I'm starting to realize that being as old as it is, this bike is likely going to need a lot of parts in the future, some are not available, and the ones that are are on the expensive side, and aren't available from dealers. It seems to take forever to get original equipment parts when you order them online. Maybe I should start considering getting another bike in the future.
The Clymer manual depicts a procedure for holding the basket and removing the nut with a large "vicegrip" type tool and others have held it with a strap wrench. Although I have read posts where the basket was broken by not using the correct tool and trying to use the ears of the basket incorrectly. (I guess that may be why I bought my EBC Clutch wrench in the first place.)

However, you can also access the pushrod from the other side by removing the clutch release mechanism sometime referred to as the little rack and pinion assembly of the forum. That way you can inspect those components and lubricate the rod without removing the basket. That procedure is also in the Clymer manual (with diagrams and pictures:)).
I finally got all my clutch parts including the oem cover gasket. I have decided not to remove the pushrod right now. Removing it from the left side requires removing the pinion shaft, and there are teeth on that that mesh with the "rack" According to the manual, there is an oil seal that can be damaged by the teeth on the pinion shaft when removing it, and that seal does not seem to be available any more. Also there is supposed to be some special tool used to protect the oil seal from damage. I removed the threaded plastic cap on the left, the one with the slot in it, and sprayed carb cleaner in there until it came out the right side. I then used an oil can and pumped oil through the left side until it came out the right side. I'm going to replace the friction plates and springs and see what happens before going any farther.
It sounds like what you have done should tell you if the rod is the problem. Over time though the use of oil instead of moly grease may actually gum up the rod and get stickie. have used some stuff from PB Blaster that is a kind of teflon/silicone lube. I use it on automobile door hinges and to lube vinyl clad house windows. it is supposed to hold up well over time. I don't know if it would work for the rod in place of moly or not.

I know I have taken my pinion assembly apart and not used any special tools. I often use plastic to protect seals when I need to. (Many timing chain covers on Fords use similar seals that can get damaged if not protested when removing them to replace a timing chain.) Usually the clear type that comes on packaging. Just cut it to the size that will wrap around the shaft real tight and slide it up past the seal

Hopefully you can get a season of riding in before you have any more problems. Good luck.
Ok, I finally got it put back together with new friction plates and springs. I also did an oil change, Castrol GTX 20w50. I prefer to use cheaper oil and change it more often. So far so good. I took it for about a 150 mile ride on the highway, and almost died from heat stroke in the process, and the clutch disengaged instantly every time I pulled in the lever. Even after more than 30 miles of highway riding without touching the clutch, it immediately disengaged. I believe the problem was caused by the clutch plates being just a bit too thick. The manual says the friction disc thickness should be 0.114-0.122 in. All of mine were around 0.124-0.125 in. I have no idea how that happened. I would think the plates on a clutch with 21K miles on it would be thinner than spec, not thicker. I'm assuming all the parts were original. I don't know why it worked fine for almost a year and a half, then started failing to disengage, and the frictions discs measured too thick. Maybe it overheated, or maybe the discs soaked up oil. I just hope it doesn't happen again. Hopefully I can get through this winter, if you could call what we have here winter, and maybe next year I will look for another bike. Seriously thinking about a Vulcan 900. Used bike prices are crazy high right now.
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Still weird.

Looked around and found some info about Emgo clutch discs being thicker, so much that leaving a steel plate out was recommended.

If thicker parts were installed, it should have been sticking immediately when assembled, and most likely forever after.

I can think of no earthly way for those discs to grow in thickness. There wasn't a ridge built up on the inner and outer edges and you measured the top of the ridges? Or they're warped?

Aliens?

They're supposed to soak up oil, I always soak them a while before installing.
They musta gotten old enough they hit puberty.
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They musta gotten old enough they hit puberty.
Oh nooo, they went all chubby!
I have no way of knowing whether they were stock or not. It had the right number of friction and steel plates. None of them were warped. Everything worked perfectly for well over a year, then it started refusing to disengage, but only after being ridden several miles without using the clutch. Still worked fine around town. In order to disengage it once it had been ridden several miles, I had to pull the lever in, then whack the throttle wide open a few times. For about a week when riding on the highway I would feather the clutch about every mile without releasing the throttle to keep it from sticking before I decided something had to be done. All I did was put in new Vesrah friction plates and new oem springs. I soaked the plates in oil overnight before installing them. I did measure the new plates before installing them, and they were just a hair over 0.120, quite a bit thinner than the old ones. If it weren't for the fact that they worked fine for so long, I'd say the old ones were out of spec to begin with, and maybe they were. That may not have been the cause of the problem. Maybe for some reason they just wanted to stick together. As long as it works right, I'm not going to worry about it. I already threw the old plates away, and hopefully this problem won't come back.
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