Hello, I have a 1985 cbx 550 f with loud cam chain rattle, i believe this to be a fault on this model, can the cam chain tensioner be upgraded or replaced with one from another model? Regards Rob

Probably a cam chain. There are two adjustments on some of those bikes. Not a simple task and needs to be done right. Get a manual.

Could be cam chain rattle. Famous for sloppy chains and inferior tensioners. Starts about 100k and downhill from there. Could try an engine flush as tensioners may be sludged. I have a 4.0L with a rattle at start up but stops after 5 seconds. Chain is shot.

Hi the cam chain is automaticaly adjusted on your bike, when the chain rattles it needs replacing or tensioner inspection

the timing chain has an automatic tensioner at the rear of the engine cylinders, if the chain is loose the tensioner is either defective or the chain is stretched to the point the tensioner can no longer take up the normal slack created by wear.

These engines use hydraulic tappets (and are good engines), so I would check your oil level is spot on (the engine oil operates the tappets). It may also be the tensioner is sticking.
Also, pull the clutch in, does the noise go away?
Good luck!

yes it is safe for you to remove the tensioner unit whilst the engine is off however Iam inclined to think from what you describethat you are due for a new timing chain

theres a cam chain tensioner in the rear of the cylinders-u need an ajustable rench or other-most important is purchase a clymer manual at bookstore or online-these ar detailed books on any problem for your kawa-viva tokyo

normaly tensioner wears first. i would replace both to ensure you dont have do the job again when the chain goes beyond its wear limits

I've got a 1995 cbr600 and it had the samr problem- it's a well known fault with hondas- it's probably the cam chain tensioner. It works off oil pressure so sounds like a tin full of marbles until the bike warms up. The best solution, if you can't live with the noise is a manual cam chain tensioner. APE make them and it stopped the noise on my bike as soon as it was fitted. I'm not sure if you can get one for your bike but a little googleing should tell you.