Clutch sticky only when hot?

[Los]

Hi guys, I've been slowly overhauling a 1989 k100 LT with 65k on it that I bought from a gent who was moving to Spain and couldn't take with him. It's a revelation, and I'm totally converted to BMW now, but I'm finding a couple of issues with the old girl. I'm finding that I have an issue with the clutch action getting very stiff and releasing too slowly only when hot. My commute to work is 10 miles, and by that 10th mile the clutch will feel harder to pull in (a bit notchy too) then when I release the lever it feels as though the plate is slowly engaging again. I changed the clutch cable, gearbox fluid and engine oil in order to try and isolate the issue. Since I've taken these steps the problem has gotten a great deal better but still bad enough to affect riding. I took a detour back from work tonight to make the journey 15 miles, and although the bike is still rideable the stickiness makes shifting and starting off very annoying. I'm totally ignorant to the servicing and adjustment of these machines, so please forgive me if this is a well known problem with an obvious fix! Any help would be greatly appreciated. Queers

[TimTyler]

Got any free-play in the clutch lever action? Like, can you lightly squeeze/jiggle the clutch lever with your fingers without actually pushing the clutch push-rod into the clutch?

Seen this thread? http://www.motobrick.com/index.php?topic=7659.0

[Los]

Thanks for the heads-up Tim, I'll double check my clutch adjustment today. It seems that the problem for that guy was the release bearing and spring, forgive my ignorance but is there any instruction for the replacement procedure on this forum? I'm struggling to find my Haynes manual! Would there be anything else you'd recommend trying first? Thanks

[Laitch]

. . . forgive my ignorance but is there any instruction for the replacement procedure on this forum?
I'm struggling to find my Haynes manual! Would there be anything else you'd recommend trying first? Thanks

Welcome to the forum, Los.

There's no need to remain ignorant. Go back to the Home page then go to the Technical Library and its Index. Scrolling through the Index you'll find procedures, videos and suggestions for many K-bike systems. You should have a workshop manual that includes your bike's model and year at hand soon but until you get one, you'll find one in the Library for models K75–K100RT to 1988. The clutch section will be relevant.

Because you write that you are "slowly overhauling"your bike, starting a thread in the Projects section with a few pictures of your bike in its current condition can help others who are interested in keeping track of the progress; otherwise, just post some in the Klassic K-bikes section.

Tim's link is the best place to start because that bike's symptom was similar to yours.

[Los]

Thanks for the information guys. I've had a guy at work (motorcycle dealership) adjust the play in the clutch cable for me. Next I'm going to try replacing the needle bearings on the actuation arm because when I pull the clutch in and then put my hand on the arm as it lowers down it feels notchy and stiff. I'll keep you updated as to how I get on. Thanks!