Motorcycle Questions? Ask a Mechanic.
Hi Dennis, thank you for your question.
If you mean the lever pressure was increasing as you rode it, that is not a symptom of a clutch that has been sitting. Does the clutch slip under spirited acceleration now? There is no real reason why the lever pressure should increase unless the pressure plate is hitting something as it is being lifted off the plates.If I am off base on my interpretation of what you mean by a stiff clutch, please straighten me out.
OK. Thank you for the clarification.
This sounds like a hydraulic problem. I would suggest starting off with an inspection to make sure you don't have any leaks anywhere. Especially at the slave cylinder. Next, I would suggest changing out the hydraulic fluid. Use a DOT4 brake fluid. There are a couple of reasons I suggest that. First, brake fluid, which is glycol based, is hydroscopic. That means it attracts water. Water in a hydraulic system can create problems. Also, hydraulic fluid should be changed at least once every 2 years, if not once a year in humid conditions, as a preventative maintenance item. The other problem that is addressed by changing out the fluid is bleeding any air out of the system.
When you said the clutch doesn't disengage, mechanically you are losing throw in the clutch push rod. This can be a direct problem of the hydraulics. Just as an additional point to make your bike as good as it can get, I would suggest taking a quick look at the brass barrel that is inside the clutch lever that pushes the rod for the clutch master cylinder. Seeing as your bike is a 1985, it could have some wear on it which also limits the throw of the clutch push rod. You do have to take the lever off the master cylinder and remove the brass piece to inspect it, but if you find wear, it will be more than worth the 5 minutes it took you to inspect it. Whether you replace it or not, make sure you grease it up so it can rotate smoothly inside the lever.
Give that a shot and if you have any more questions, feel free to ask.