JLamb
1991 ST1100
91 ST1100 w/ 80K miles. Overall the bike runs pretty good. Seems to have good power, pulls to RL without any noises, hesitation etc. Doesn't use oil. However - when I rev the motor with the clutch in or in neutral there is a loud sharp snapping noise that seems to be coming from the exhaust - or rather happening inside the exhaust. It sound like a really fast hard metal to metal snap. Several occur each time the throttle is twisted. It doesn't sound like knock - maybe detonation? But at the rate they occur I think detonation would have caused some damage by now? Any ideas?