Has anyone heard of any engine issues with these bikes? If so what is failing? I have a friends bike has 4000 miles, he was on the high and engine stopped making power, now it is make noise a tapping noise? I checked the valve clearances and they look good so no broken valve? Just look for some ideas before the motor gets torn down. Thank you Kent
it doesn't sound like your problem, but a racer friend of mine, wera ne #427 broke a crank at summit earlier this year. i ride suzuki.
A buddy of mine 636 just had a piston slap a valve and destroyed his engine. Holes in the front and rear of the engine case.