Clutch 'seized' or 'stuck'

I just watched the video I posted, and my description of how the clutch functions from the lever, is quite weak. By stating "theres just nothing there", it sounds as though it feels as if the cable were attached to nothing. That, however, would be a wrong assessment of what's going on. In reality, it feels as though the cable were attached to a brick wall. I can not move it. Again, this is only when the pressure plate is installed. Everything seems to move freely without the pressure plate. And yes, the dot on the clutch boss does line up with the hole on the pressure plate.
 
Put in the ball bearing, then report.
This is typical adjustment screw "stick out"
If your screw isn't at about that length somethings not right.
Check the nylon spiral in the worm They can crack especially if excessive force has been used.
 

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Your worm install looks correct. Once fully screwed in, you want the arm to end up pointing to about the 7:00 position. To achieve that, start screwing the worm in with the cable arm pointing to about the 3:00 position .....

InstallStart.jpg


The arm will need to be rotated up about 1/2" to connect the cable and then will end up in about the 8:00 position. Once all adjusted up, you want the angle between the cable and the arm to be around 90° as this gives the best leverage when you pull the lever. Ideally, an angle slightly less than 90° is best so the arm moves through that 90° point as you pull the lever in and ends up slightly past it. Here's the stock worm on my '83, installed correctly and all adjusted up .....

StockWorm.jpg


Now, here's a screen shot of yours I pulled from your video. Cable attached and (I'm assuming) adjusted up, your cable arm is way past that ideal 90° point .....

MissingBall.jpg


So yes, I agree, I think you've lost the ball out of the worm. When you do the clutch adjustment, you start by screwing the adjuster up at the lever all the way in, putting as much slack as possible in the cable. Then you adjust out as much of that as you can down at the worm. You can get most of it, but not all, with that worm adjuster. You finish with just a couple of turns out at most up at the lever. Adjusting down at the worm doesn't change the angle between the cable and the arm but adjusting up at the lever does. This is why you want to do as much of your adjusting as possible down at the worm, so you don't lose that ideal 90° angle between the cable and arm. Here's another screen shot from your video showing the lever adjuster up at the bar. It's screwed out pretty far and I think that's why your angle between the cable and arm is so bad .....

LeverAdjuster.jpg


Here's mine, and as you can see, it's not screwed out very much at all .....

83Installed.jpg
 
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Your worm install looks correct. Once fully screwed in, you want the arm to end up pointing to about the 7:00 position. To achieve that, start screwing the worm in with the cable arm pointing to about the 3:00 position .....

View attachment 226695

The arm will need to be rotated up about 1/2" to connect the cable and then will end up in about the 8:00 position. Once all adjusted up, you want the angle between the cable and the arm to be around 90° as this gives the best leverage when you pull the lever. Ideally, an angle slightly less than 90° is best so the arm moves through that 90° point as you pull the lever in and ends up slightly past it. Here's the stock worm on my '83, installed correctly and all adjusted up .....

View attachment 226697

Now, here's a screen shot of yours I pulled from your video. Cable attached and (I'm assuming) adjusted up, your cable arm is way past that ideal 90° point .....

View attachment 226698

So yes, I agree, I think you've lost the ball out of the worm. When you do the clutch adjustment, you start by screwing the adjuster up at the lever all the way in, putting as much slack as possible in the cable. Then you adjust out as much of that as you can down at the worm. You can get most of it, but not all, with that worm adjuster. You finish with just a couple of turns out at most up at the lever. Adjusting down at the worm doesn't change the angle between the cable and the arm but adjusting up at the lever does. This is why you want to do as much of your adjusting as possible down at the worm, so you don't lose that ideal 90° angle between the cable and arm. Here's another screen shot from your video showing the lever adjuster up at the bar. It's screwed out pretty far and I think that's why your angle between the cable and arm is so bad .....

View attachment 226704

Here's mine, and as you can see, it's not screwed out very much at all .....

View attachment 226706
Thanks a ton for your input! Finally free for the day and able to go work on it. I will follow your advice and check back in. Thanks.
 
To determine for sure if you've lost the ball out of the worm, take the adjuster screw right out. If the ball is gone, you'll be able to look right through the worm.
 
I am going to try my hardest to post things all in chronological order, and bring you up to speed.
 
20221002_171756.jpg

First things first, I checked the worm gear for the hidden ball bearing. It is there. In the first video, you will see the worm gear set up, as suggested, 'one notch anti-clockwise', and the cover would not close. I then followed 5twins method of installing the worm gear, which was how it was originally, and it fit fine. You will see in the video, how I did in fact get the arm on the worm gear to run perpendicular with the direction of the cable (90 degrees or so). I also completely disassembled the worm gear assembly, and thoroughly cleaned it out. In reassembling the worm gear, I copied 5twins pictures, and greased the worm gear arm, and the ball bearing area. I used some marine spline grease that my grandfather and uncle (whom is a world class boat mechanic) swear by on applications such as this.
 
I will also add that the worm gear seems to be in near perfect condition. No cracks, chips, and functions smoothly.
 
I also found out later on, that (although I didn't like doing it) I could disengage the pressure plate via over tightening the adjuster screw. It's a bit of a tough turn, but to me, that also showed, that the problem does not lie in the cable, or the lever. Pushing the pushrod via the adjuster screw, is easy with the pressure plate removed, but tough with it installed. Same as with the cable and lever.
 
As you can see from this video, the clutch appears to work as intended when tested with the pressure plate removed. I will also add, that with my body weight on the pushrod, as seen in the video, the clutch lever shows next to 0 resistance. It moves very smoothly.
 
I did not end up taking another video with the screws loosened. However, I think you should all get the point. Since these videos, I've gotten the clutch to work just by simply working the adjuster screw a bit with the assistance of the cable. I don't like doing this, as I don't want to put too much stress on the worm gear. After supper, I may just take the bike for a gentle short cruise and see if I can work things a little looser. I can at this point get the clutch to function from the lever, however, it is a very very stiff pull.
 
When I talked about the arm on the male worm pointing to 3:00, that is the starting position for screwing it in. Once fully screwed in, the arm should end up pointing to about 7:00. You installed it with the arm pointing to about 3:00 once the worm was fully screwed in. Then you had to wind it back out nearly a half turn to hook the cable into it. That raised the male part up and that's why the cover wouldn't fit back on.

You need to oil a new clutch cable as they come almost dry and will give a very hard pull, binding up big time when you put a load on them. The first one I ever replaced pulled harder than the old one it was replacing because I hadn't oiled it. These bikes are known for a rather stiff clutch pull, but not as bad as yours, lol. Someone may also have installed too heavy duty springs. There are several aftermarket sets available and some are much stiffer than stock (like 50%). Keep the cable well oiled and make sure the cable routing has no sharp bends in it.

To tell if your springs are heavy duty replacements, you could measure the free length. Stock springs for your model clutch (7 friction plates) are 34.5mm long. Aftermarket heavy duty ones are usually longer.
 
I did not end up taking another video with the screws loosened. However, I think you should all get the point. Since these videos, I've gotten the clutch to work just by simply working the adjuster screw a bit with the assistance of the cable. I don't like doing this, as I don't want to put too much stress on the worm gear. After supper, I may just take the bike for a gentle short cruise and see if I can work things a little looser. I can at this point get the clutch to function from the lever, however, it is a very very stiff pull.
Certainly an unusual problem. If the lever pull is hard for you - a bricklayer - most of us couldn't use it. The assembly appears correct in the recent pics and video. You appear to get about the right amount of movement without the pressure plate. You're right about over-tightening the worm adjuster - it'll break.

Have you removed the pushrods and checked them for damage and also check the bushing for binding? Unusual step, but unusual type of problem.
 
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Yes, pull the pushrod(s) out and inspect. There should be balls in that assembly line too, one between each rod and one at the end under that little pusher part .....

Clutch Balls.jpg


I'm not sure if your model year had the 2 piece pushrod set-up as shown above or still used the long one piece rod (it would replace the 2 rods and the ball between them). Both would have a ball at their end between them and the pusher part. Assembly should be rod-ball-rod-ball-pusher part. Wherever 2 rods meet, there should be a ball between them. The adjuster screw can also be considered just a very short rod and that's why there's a ball between it and the 1st pushrod. Maybe someone put 2 balls together? To check if the assembly does have the correct amount of balls, you can measure how much of the pushrod sticks out of the case. It should be about 48mm .....

OutsideLength.jpg
 
When I talked about the arm on the male worm pointing to 3:00, that is the starting position for screwing it in. Once fully screwed in, the arm should end up pointing to about 7:00. You installed it with the arm pointing to about 3:00 once the worm was fully screwed in. Then you had to wind it back out nearly a half turn to hook the cable into it. That raised the male part up and that's why the cover wouldn't fit back on.
Yes, I understood how you explained it, as you were very clear. How you explained it, was how the worm was set before I had adjusted it. I simply tried adjusting it 'one notch anti-clockwise', as it was a potential solution to the problem. However, I did install it properly after, and was able to install the cover.
 
You need to oil a new clutch cable as they come almost dry and will give a very hard pull, binding up big time when you put a load on them. The first one I ever replaced pulled harder than the old one it was replacing because I hadn't oiled it. These bikes are known for a rather stiff clutch pull, but not as bad as yours, lol. Someone may also have installed too heavy duty springs. There are several aftermarket sets available and some are much stiffer than stock (like 50%). Keep the cable well oiled and make sure the cable routing has no sharp bends in it.

To tell if your springs are heavy duty replacements, you could measure the free length. Stock springs for your model clutch (7 friction plates) are 34.5mm long. Aftermarket heavy duty ones are usually longer.
Yesterday when working on the bike, I did a check for the free length of the springs. Every one of them measured 1.35+ inches, which I believe is the imperial measurement for them? I believe there was one that was 1.36-1.37 or something. But nonetheless, all within reason. Whatever the imperial measurement is, my springs were a match haha.

However, the oil suggestion intrigues me... It could be embarrassing for me if that was the fix, as I knew/know they are to be oiled, via my books and reading online. However, because it pulled so freely without any load, I placed that further down the totem pole of importance... However, I see exactly what you are saying, and understand how under load, it could act completely different and cause the cable to, as you say, bind in the cable housing (or whatever you'd want to call it?). I will oil it tomorrow for sure. A part of me hopes that's the fix... And a part of me hopes it isn't... It will be one of those "I should have known better, and listened" moments...
 
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