86 VF500 Clutch issues

Hi everyone,

So, my vf500 is running pretty well now after several months of work and a lot of help from you guys.

My last issue is my clutch. When I hold the lever down all the way and put it into gear the bike lurches forward and dies unless I give it some throttle as I do it, like "blipping" the throttle on a down shift.

It still kind of wants to roll forwards with the lever pulled all the way to the grip but I can hold it with one foot on the ground or either of the brakes. It also won't shift while stationary in to neutral or any other gear if the bike is running (it's completely smooth and happy to shift if the bike is off altogether).

But here's the fun part, I can let the lever out 90% of the way with no change in the amount of pull from the engine and then I hit the "proper" friction point of the bike and can set off normally. I can change gears while moving at a reasonable pace but the shift lever still feels stiffer when I upshift as I'm driving than if I turn the bike off altogether and cycle through the gears.

I have:

No leaks in the hydraulics
Bled the clutch lines and topped up the master cylinder

I'm thinking that the clutch plates may be warped? But that's honestly just a word I read out the FSM and I have no idea what that really means.

Guidance would be appreciated

 

a clutch that isn't fully releasing can be caused by warped plates (usually owner abuse) or by a poor job of bleedin, or old, tired fluid. :confusion: Try removing slave cylinder from the sprocket cover and holding the piston fully retracted with a C-clamp while you bleed it again. layful:

 

Thanks for the quick reply

Interesting advice on the clutch bleed! By sprocket cover to you mean the whole left engine cover?

Have you ever worked on the clutch plates before? I'm willing to replace them but as I understand it, there are two types of disks in there. Half are "friction plates" and the other half are "clutch plates". According to the FSM the clutch plates are thin pieces of steel and the friction plates are actively abrasive. The friction plates I can get in a kit with a fresh set of springs for the pressure plate and a new gasket for the engine cover on the right side for $45 USD. It seems to be much more difficult to get the steel plates in between. Which of those disks commonly warp (or both)? Should I be replacing the steel disks as they're 10-15 bucks each and I need 8 or 9 of them.

 

It's the steel plates in the clutch that warp when overheated (owner abuse), not the friction plates so much. Since your clutch isn't slipping, you don't need new friction plates. Your clutch mc may need replacement if it won't build enough pressure to fight the clutch springs..........or may just need fresh fluid and a properly-done bleed.

 

Hey thanks squirrelman,

I think the abuse may be my doing to be honest.. This is my first bike and I learned how to drive a manual transmission on this bike over the last month or so and I've stalled it quite a few times.

I'm going out to the shop on sunday to do some work on it. I'm still unclear as to what the "sprocket cover" is though as you mentioned in your first comment. Do you mean the left crank case cover? I'm going to try your bleeding trick before going at the right side cover to get to the basket and plates.

Thanks again.

By the way, I was able to do the carbs with my dad and the bike runs great now. Thanks for your advice on that one too a few weeks ago!

 

So, I've gone ahead and bled the slave as you suggested. I figured while I had the oil out I might as well pull the right crank case cover and check on the plates. Once I got in there I noticed the gasket was lime green and had evidently been replaced recently, the clutch also appeared to be pretty new. For anyone who was unaware at this point, I bought this bike off of kijiji and I'm nursing it back to health.

I noticed that there was a set of barnett friction plates in there which appeared to be pretty new. There was also one oddball friction plate (for a total of 9 friction plates) which was a little thicker (3.42mm) than the others.

According to the factory service manual there are two little rings that should have been in there at the bottom of the basket (I believe they are the "Judder spring and seat") does anyone understand the function of these? I didn't have them and I'm assuming I should get some.

Looking at the diagram closely I see that the first friction plate that goes in to the basket should have a larger inner diameter than the rest of them, mine (the odd one out) most certainly does not. I assume I should also be hunting one of those down?

I checked all of the steel plates one at a time with a feeler gauge as the FSM suggested, they're all in really good shape and look almost new.

One other thing I noticed, there were slight ridges being worn into the fingers of the clutch basket where the friction plates bite. I've heard of that causing similar issues on dirt bikes because when the clutch is engaged and the friction plates bite the basket they can sometimes create little grooves. Then when the clutch is disengaged they stay in those grooves (and therefore won't separate properly). Does anyone know if that could be my issue here?


Thanks!

 

For anyone who stumbles across this thread in the future, I resolved my issues and I've documented how in this thread:
http://vfrworld.com/forums/showthread.php/49155-How-to-fix-a-quot-Dragging-quot-86-VF500-Clutch