Sticky, over sensitive clutch

[ptm]

77 GS400, 8000 mi, always garaged and well cared for. For the last 500 miles or so the clutch has gotten very sensitive - it's hard to modulate at the friction point. Not a problem going from 2nd - 3rd and beyond, but a smooth start in 1st is very difficult. My hand cramps from trying to let the lever out smoothly if I have to stop frequently. It seems binary - it's either released or not, there's no in between.

Just sitting with the engine off and moving the lever in and out, the lever feels like something is sticking - it's not smooth like my other bikes. As I slowly let it out I can feel it kind of stick and release. I've cleaned and lubed the lever pivot and cable - although neither looked like they needed it. And I greased the clutch release screw that the cable turns on the side of the case. No joy. If the side cover is off, the lever, cable and release screw work smoothly, but there's no load on them since they are not actually pushing the shaft which pushes against the clutch springs.

Before I pull the clutch apart (or even after), any ideas what the problem is or what I should look for?

Thanks

 

[koolaid_kid]

With that few miles, I would look for sticking plates. They could very well be glazed, and just need to have the glaze knocked off. Still requires that you remove the cover, but not very expensive in money, just in time.

 

[ptm]

Thanks for the reply. I have the cover off, but didn't want to go deeper unless I had to. Are you talking about the fiber or metal plates, or both? Is the glaze obvious once I get it apart? Just sandpaper on a flat surface to knock it off? Any grit suggestions? What would cause the plates to glaze?

Questions, questions, questions...

Thanks again

 

[Guest]

<<<I've cleaned and lubed the lever pivot and cable>>>

Does this mean you checked the entire length of the cable from one end to the other?

 

[ptm]

Does this mean you checked the entire length of the cable from one end to the other?

No, I don't think there's any way to remove the actual cable from the sheath to do a real inspection and clean, but I did run a pile of cable lube through it. I think I lubed it before, sometime over the last 33 years, but I'm not sure. I should take a look through the records to see if I wrote it down.

I have a new cable, but I hate to replace the current one if it's not the problem. And I don't want to fatigue the tab that keeps the cable from coming off the holder by the release screw unnecessarily.

Thanks again for the replies.

 

[Guest]

I'd clean the clutch plates since its already apart. Maybe with a red scotch brite pad? Wash em with soap and water and slap it all back together. If it still gives ya grief replace that cable. By the way, what did ya use to lube the cable?
This one would give me fits too cause for some reason it seems like something external.

 

[koolaid_kid]

Thanks for the reply. I have the cover off, but didn't want to go deeper unless I had to. Are you talking about the fiber or metal plates, or both? Is the glaze obvious once I get it apart? Just sandpaper on a flat surface to knock it off? Any grit suggestions? What would cause the plates to glaze?

Questions, questions, questions...

Thanks again

Both. The only way to tell is to buff one out. I prefer to do it this way: Get a very flat surface (glass is best). Place a piece of 600-1000 grit wet-r-dry sandpaper on it. Wet it with water or oil. Place the metal plate on it and go to town, relubing occasionally when required. When it is nice and shiny, compare it to another. If there is not much difference, they may not be glazed, but I'm betting they are.
I also try to deglaze the fibers as well, but take a lot more care because you don't want to remove the actual fiber, just the glaze. And only use oil on the fiber plates, water will make them swell.

 

[ptm]

Both. The only way to tell is to buff one out. I prefer to do it this way: Get a very flat surface (glass is best). Place a piece of 600-1000 grit wet-r-dry sandpaper on it. Wet it with water or oil. Place the metal plate on it and go to town, relubing occasionally when required. When it is nice and shiny, compare it to another. If there is not much difference, they may not be glazed, but I'm betting they are.
I also try to deglaze the fibers as well, but take a lot more care because you don't want to remove the actual fiber, just the glaze. And only use oil on the fiber plates, water will make them swell.

Thanks. I'll dig in and see what I find. I need to take the cover of that side of the engine anyway. It's the only part of the engine where the clear coat has yellowed and I want to deal with that, too.