Topic: Timing chain on CB550

[70CB750]

This guy I know has a new to him 74 CB550.  He is concerned with the cam chain, says it's noisy in idle.   I know on 750 the cam chain sounds quite noisy, too. 

Is the noise normal for 550?  Does it need cam chain replaced at certain mileage?  Any known problems with the tensioner?   I never touched 550 - hence these questions.

[Scott S]

 They make a little noise. More likely, it's the primary chain.
 You'd be amazed what a cam chain/valve adjustment and vacuum synch will do to quiet them down.

[craz1]

How many miles, and how they were maintained in the first place will make a difference. I would go through the cam chain adjustment and the valve adjustment first. I think a lot of people have problems with the 550 cam chain adjustment and don't understand how it works and screw up the adjuster. Be aware of that and get a manual. Also that year still had the 8 individual rocker shafts which are not pinned and tend to wallow out the shaft bores making it impossible to properly adjust your valves which will add to the noise. I rebuilt my 74 a few years back and replaced the cam and primary chain and used the later 78 pinned cover and shafts, my bike is very quiet. If you go to that extreme also use the APE cylinder studs when re-assembling.

[70CB750]

Thank you.   I will pass it on.

How about primary chain?  I never dealt with it on my bikes, is it better to replace adjuster just to be on the safe side?

[bryanj]

There is no adjuster on primary chain, if the cases are split change it and the primary damper rubbers as the 500/550 have a hard life. Kawasaki primary is half the honda price, part number is in multiple posts