When riding my 1990 cbr600f in a high gear at around 4000 revs the bike is making a horrible juddering sound. Do you reckon that this could be a serious problem ? I’m not sure if this is a misfire, a rattle , a knocking sound or blowing sound. Any help would be good

 

Does it go away if you pull in the clutch? does it change when riding vs stopped? Does it get faster with revs?

 

Does it go away as the revs climb?

 

​​​​​​Cam chain tensioner will make all kinds of noise at higher RPMs but you'll also hear it when it's idling and they are known to go out simple fix unless you have to go internally and replace the runners