running rough

[tony g]

i just put amr stage 3 cdi box on my bike and its running rough like its missing at idle and when i ride it it pops and backfires when i let off throttle it ran fine before i put box on its a 416 with 11.1 piston stage 2 hotcam full curtis sparks exhaust open airbox 175 main jet can anyone help me out

[CJM]

Send the box back, its junk. All CDI's are junk basically for the 400ex b/c they basically use an XR250 box and it doesnt work right most of the time.

[DragonGunner]

If it runs fine with stock cdi then its probably the new cdi you bought.....I got one of the early White Brothers CDI's that works great and is alot better than the stocker by far.

[Zakradu398]

Originally posted by DragonGunner
If it runs fine with stock cdi then its probably the new cdi you bought.....I got one of the early White Brothers CDI's that works great and is alot better than the stocker by far.

I believe the early WB ones are stock xr250 cdis..

[DragonGunner]

This could be true.....however I can find no facts, just opnions that this is a fact....? Does the xr250 cdi look exactly like the 400EX stock cdi......? The WB I have looks like the 400EX stock cdi, and etched WB on it. It was my understanding that WB were taking stock CDI and re-programming them....I have also heard the claims that CT racing just sells xr250 cdi as their own also.....? Either way I love what I got from WB, it simply performs way better than stock.

[Zakradu398]

Pretty sure all it does is either raise the rpms or delete the limiter. Others affect the spark timing..

[CJM]

Originally posted by DragonGunner
This could be true.....however I can find no facts, just opnions that this is a fact....? Does the xr250 cdi look exactly like the 400EX stock cdi......? The WB I have looks like the 400EX stock cdi, and etched WB on it. It was my understanding that WB were taking stock CDI and re-programming them....I have also heard the claims that CT racing just sells xr250 cdi as their own also.....? Either way I love what I got from WB, it simply performs way better than stock.

I got the same one, WB sticker on and and etched with WB. It performs really well vs a procom I tried that basically caused the quad to run like crap and have no power.

[DragonGunner]

My WB never had a sticker.....and the one I have has a different power curve also, beside being able to rev more on rpms. When I got mine it was the only aftermarket CDI that I knew of.....now there seems to be alot of different ones that got in on the market for a fast buck that just don't perform.....?

[JOHNDOE83]

WB is the best rev box by far, ive tried several different kinds and WB is deff more noticeable.

If you have any timing mods a rev box will not work right, some will some wont.

If it rides fine with the stock rev box then send yours back and get a WB rev box.

[tony g]

i always hit rev limit with stock box running 14/36 gearing

[JOHNDOE83]

My fire breathing 440ex monster with a WBs cdi never hits the rev limiter and revs all the way to hell and back.

[tony g]

maybe i need a wb box anyone got one for sale

[Longdong]

Originally posted by tony g
i always hit rev limit with stock box running 14/36 gearing

Your answer is....... Change your gearing!!!!!