hi there guys, i need some help, iv just passed my bike test and bought a fzr 600 iv had the bike about 2 months now and had this on going problem, well its got a problem when i rev it on the spot it goes round to 9000rpm then pops and spits a flame out the exhaust it only does it at wot if i rev it gently it will go all the way up too the redline, it also does it while riding it and is very frustrating, the carbs have been cleaned and i checked what jets are fitted (all standard ) the needles have 5 grooves (set at 2) and mixture screw set at 3 turns out, iv not synced them as iv not got acsess to a sync tool, spark plugs are new, air filter is new, any help would be very much appreciated

Sounds like a valve timing problem to me - have you checked and reset the valves?

Pops and spits are mis-fires. There is something faulty with the ignition system. Try changing the spark plugs for new ones.

Sounds like a valve timing problem to me - have you checked and reset the valves?

Pops and spits are mis-fires. There is something faulty with the ignition system. Try changing the spark plugs for new ones.

iv not checked/reset the valve clearances yet, does anyone have a guide to to it and the settings?

the spark plugs are new iv just replaced them, im thinking ignition problem now aswell but dont know what/where to check