Bad missfire/flames *Please watch video*

[Rapture]

I have a Stomp Z2 which i have just done the valves on. Timing lined up spot on all and everything went fine. Fired second kick.

It Idles lovely, but under heavy accelleration and perticularly under load it has a horrible missfire (im assuming this is what it is). Flames shoot out the back on throttle (not decel). On the first ride at the start it wasn't too bad, after 15 mins of riding it got way worse and wouldn't even go past quatre throttle and just dies on me.

I've changed plug, cleaned carb 2 times, cleaned tank and filters.

I never saw the bike running before i did the valves (bought cheap as non runner).

I beggining to think its a ignition problem. Please see videos and let me know your thoughts. Much appreciated!

https://www.youtube.com/watch?v=6MPgWopYTLY

https://www.youtube.com/watch?v=hWAziAU2aHI

[Pitbikeowner101]

Originally Posted by Rapture

I have a Stomp Z2 which i have just done the valves on. Timing lined up spot on all and everything went fine. Fired second kick.

It Idles lovely, but under heavy accelleration and perticularly under load it has a horrible missfire (im assuming this is what it is). Flames shoot out the back on throttle (not decel). On the first ride at the start it wasn't too bad, after 15 mins of riding it got way worse and wouldn't even go past quatre throttle and just dies on me.

I've changed plug, cleaned carb 2 times, cleaned tank and filters.

I never saw the bike running before i did the valves (bought cheap as non runner).

I beggining to think its a ignition problem. Please see videos and let me know your thoughts. Much appreciated!

https://www.youtube.com/watch?v=6MPgWopYTLY

https://www.youtube.com/watch?v=hWAziAU2aHI

Hi mate, first you have removed the videos and second have you checked plug colour while bike was warm if not it should be browny colour sounds like you could be running lean to me

Or rich.... i had a funny problem like this where my wpb would backfire pop shoot big blue flames out the exhaust the cause was a leaky intake valve so id check that and it might be a good idea checking the clearences intake 4 thou exhaust 6 thou

Hope this helps