my tt600r back fires when i rev it up hard and when i am on the overrun, it starts up ok and runs fine until i have it flat out and it appears to misfire or is it valve bounce? this is the first big four stroke single i have owned and wondered if this is normal? it is a 2001 model with 11000 kms,any comments would be most appreciated thanks carl.

Do you mean popping or proper backfire (loud bang like a gun) ?

If its like popping then dont worry, heavy popping is probably a lean mixture caused by a race can etc.

Whats the set up ?

__________________
www.touringted.com.

Its A Proper Back Fire If Its Dark You Can See A Flame The Set Up Is Standard From New

Check you filter is clean, change the spark plug, check your valve clearances and then if still no better, overhaul your carb.

__________________
www.touringted.com.