trebloc

Thank you for your quick reply I have checked all the ignition circuit and spark plugs for the correct firing and all is ok. I have even changed the two coils around and the same problem persists in the same cylinder. Today i have done a compression test and all the readings are 140psi which is very low. I wouldn't of thought the pistons or rings are worn because it has only done 9500 miles.

I have a Yamaha FZS Fazer 600 1999. I have noticed that when started the exhaust downpipe from number two cylinder never warms up. I assume that the combustion in that cylinder is faulty. I have checked the spark plugs, ignition system, valve clearances, carb sync etc and everything is ok. If you have any advise please let me know.