I've noticed a very slight knocking noise that is only audible when just coming off idle. It isn't there whenidling, just when the throttle is cracked open a little and then it disappears. No noise at all above 1100 RPM. It is more noticable when the engine is cold. Changed from Harley 60 wt. oil to Redline 20W60 with no effect on noise. Compensator nut seems to be tight. There is a little bit of black greasy residue around the comp on the inner primary case. Can't tell ifthe noise iscoming from the engine or the primary. I just got the bike and have ridden it about 1000 miles with no change in noise. It's almost not noticeable at all - but it's there.

Thanks in advance to all respondents!

John

 

Well, it turned out that I was hearing the intake valve on the rear cylinder popping open! The sound was coming out thru the air cleaner. Never had that happen before. Sounded just like a knock, but when I covered up the air intake with a towel, it dissappeared. Learn something new every day I guess.