Engine rattle

[colab]

72 cb750K

My mechanic has rebuilt and sync-ed the carbs and replaced the manual tensioner. He says he’s still concerned with the engine noise.


Sounds like much of the noise is from the clutch basket. Perhaps he’s hearing something different in person than I am getting from the video.

My guesses are:
-worn/warped clutch plate
-need to replace primary chain
-Cracked carb boots throwing carbs out of sync.

Has anyone here experienced the same with a cb750k?

 

[irk miller]

Are the carbs perfectly synced and do you have the rpm's really low? Not uncommon for the clutch to rattle when the idle is low and the carbs are out of sync. Get it smoothed out and see if it quiets above 1200 rpms. I put 15k on a CB750 that did the same thing.