backfires when i let off the gas?

[speedy]

I got a 400ex and it runs good when you hit the gas but when you let off it kindy backfires alittle like when im goin down hill it does it alot what does this mean or is it even anything to to worry about??:confused:

[speedy400]

Do you have a high comp. piston and a pipe? if you do thats normal for it to do that a little. If not its really no big deal, its just kinda annoying(to me I think it sounds awesome but thats just me.) usually you can get rid of it by richening up the pilot 1 size and if that dosnt work richen up the air/fuel screw.-darren

[mikes450r]

my 450 did the same thing after i put in a new cam

[speedy]

Ok, cool i wont worry bout it then.:D

[Toadz400]

A friend of mine's 450R does that, he just put in the HRC kit.

If it's backfiring, you're most likely running too lean. Try richening up a bit and see if that helps.

[Hammer trx450r]

You need to turn your air screw out quarter turn untill it stops.

No its not normal

[400-416EX]

Check your jetting

[speedy]

I dont remember if i have to take the carb off to get to the air screw so if anyone knows if i have to or not tell me ???????

[nosliw]

Originally posted by speedy
I dont remember if i have to take the carb off to get to the air screw so if anyone knows if i have to or not tell me ???????

to get the to fuel screw you dont necessarily have to take off the carb. i can get at it with this motion pro tool which is like a screw driver with a 90 degree bend. but unless you feel like blowing $30 like i did i would just take it off.

[Hammer trx450r]

I use the screwtip from a screw gun, nice and small. Put your head on the floor and look up at the carb and u will see it

[ewalker302]

Get yourself a cheap lil screwdriver, then just saw the handle off, so you can get to the screw easy.

:bandit:

[speedy]

alright that fixed it. thax ever 1