new 05 400 ex cutting out and stalling

[charles]

have 05 400 ex and havenot had first service.only have about 12 hours riding time and this thing is sick.sputtering and back firing.

[Fred55]

sounds like something with the reverse rev limiter is messed up?

[400exredrider]

you should have atleast changed the oil after 2 hours of break in

[xrkiller]

as dumb as it sounds is your choke open?

[04'400ex'er]

cud be water in the gas, fouled plug, dirt or metal in the main jet. change the plug, then try it. if that doesnt fix it then remove the carb and clean it. float could be sticking. also drain the tank and put in fresh gas.

[prepracing]

do you have any modifications ? airfilter clean ? carb. sitting level and clamped tightly ?

[400exredrider]

really shouldent be having problems... if its under warranty id take it to the dealership.

[prepracing]

10-4 that, let the dealership have the headache !

[6858-400ex]

if u just bought it it should be under warranty

[bwamos]

And, if you replaced anyhting with aftermarket (like pipe, filter, jetting etc.) make sure to put it all back to stock settings, or they will void your warranty.