Yamaha WR450 supermoto backfire flames

[outlwd]

High octane petrol with octane booster does that also

[fireyphoenix1989]

what is it with every twat and monster stickers ........they look tacky as fuck :( so many bikes looks being ruined by them

[kev22bmx]

i have a 125 4 stroke motard and it does the same when the engine is hot..spits fire..its the pipe that does that

[mcrdrummer]

ur gonna spoil ur engine soon

[Joshnio]

@mcrdrummer Why is that? Backfire is merely the combustion of unburnt gases etc from the engine and shouldn't do fuck all harm. If his bike's cold as he throttles it in this video I agree

[danicksta09]

dude that is not good but it's fucken awesome !!

[chrisssss89]

man your bike is wreck...thats why is doing that...its takes more air that is need

[jansen709]

its a FmF power core 4

[Yamiboy2]

im pretty sure its a fmf

[DR1ZERO]

@Yamiboy2 It is a FMF Powercore i have one just like it on my XR400 and it does the same thing. I like to start the bike, open the air on the carburator and start riding it before its completly warmed up because it starts BURRRRRRRAPLA RAPLA RAPLUM when i hit the gas and shift gears up i think you can almost light up a cigar on that :D

[nutbraker]

looks like akrapovic

[yz125and85]

What exhaust is that?

[dax446]

i've had the timin done and jets set, its just the pipe that makes it do that

[buzzender]

@dax446 no its not, set your fuel air mixture, my yz250f did that until i set the carb up correctly, runs beautifully now.

[moresiky]

que llantas llebas montadas? esque nose cuale le valen