Hi used to ride bikes alot years ago. 4 months ago got started again after 15 years with 1999 CBR600 f4 25.000 miles on the clock.

At first i didn't notice the vibration because I have been away from bikes for so long, stiil getting used to the buffeting of the elements, but As the weeks turned into months i noticed the vibration between 5000 and 6000, so much so that it numbs my nuts, and loosens the crash pins at the end of the handle bars.

I rode a couple of other f4's and they seem smooth at those revs. I am really disappointed, and worried something horrible might happens if i don't take the appropriate action in time.

Any idea as to what might cause this.

 

if its making a loud clanging noise its the tensioner. i had a f4i and they all have recalls on the cam chain tensioner.