Hi all,

I own two Yamaha TT600's, one in rebuild the other running....well hmm sort of....anyway my issue is this, the bike starts easy,idles perfect but when going over 60km's per hour or when you start gunning it, the bike changes completely, she starts backfiring and gosh knows what else ....it really sounds like a timing issue when you rev itr high...

Changed the following :

CDI,coil, stator, carbs.....to no avail, i cannot understand this problem...building engines is a walk in the park but this bike is killing me lol

Any comments would be highly appreciated..

Frank

Had a similar issue with my XT600 Frank.....

Check the condition of your carb manifolds.....if they're cracked, they'll suck a fair amount of air through there & cause the backfiring you speak of.

I was advised to reseal the mounting surfaces between the carb boots & the cylinder head with a thin coat of RTV gasket sealer.....as my boots were in great shape......this did cure the problem.

Might be worth a try....

Best of Luck with 'em

Oh, & BTW..... to the forum!

Helped a bloke out on a Triumph Bonneville the other day with similar issues. Bike had been stood for some time whilst engine mechanics were sorted. He had taken it for a 'proper run' and had died backfiring and poping to the side of the road. He was not happy.

Me and my Daughter pulled up to help, could not carry on past and leave him stuck on a DC with a clear concience.

We used the car as a blocker.

The cracks in his inlet rubbers between the carb and the engine were clear to see.

Got it going but only on full choke and he nursed it home.

Hi all,

Thanks for the replies to date....great to know someone is thinking on this issue with me, i'll checkout the boot rubbers today and get it solved.

Thanks again in advance.

Frank

CHECK YOUR MAIN JET FOR PLUGGING

Well done airman, but check the date