QuestionI have a 1982 CB 900 Custom with 50KM's and wondered about the cam chain tensioners with this mileage. I have adjusted a couple of times and not noted any difference. What is the normal mileage you could expect before having to replace the tensioners? There is some clutch basket rattle typical of these motors with some mileage, so it is hard to determine how noisy the chains really are.
AnswerDavid, I would pull the valve cover and check the camchain tension visually. You can rock the crankshaft back and forth, watching the cams as they move back and forth in synch, if the camchain is tight. Otherwise, you will feel and see a "delay" between backwards and forwards motion of the crankshaft. If so, loosen the tensioner and see if it will tension the camchain or not. Camchains can get worn and move on the sprockets, as well as be sloppy between the sprockets.
Check and adjust tension on the rear chain first, then do the front one to the exhaust cam.
The bike is 27 years old now and stuff is bound to wear and degrade over time. If the chains are climbing the sprocket teeth and the adjusters aren't responding, then you may have to go in there and replace some parts. Cam chains are endless, so that usually requires a full motor teardown to loop them over the middle of the crankshaft.
Clutch rattle is often a combination of uneven compression, carbs out of synch, primary chain slap and some wear in the clutch assembly.
Bill Silver
