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400exrider21
12-17-2012, 08:05 PM
im going to rejet my 01 400ex and i pulled out the jets and realized that the main jet was a 118 and it has the keihin logo on it so i assume its keihin brand but online it says stock size is way bigger?? what do you think also the pilot jet is a 38 thanks
:confused:

400exrider21
12-17-2012, 08:09 PM
here are the mods if this helps
k&n airfilter with precharger
ground down header welds lexx slip on
on the intake boot (carb to motor ) i ground down the boot to match the intake on the head and sanded it smooth
the casting marks are removed and poliched up in the intake side of the head! thanks again and what shoul my jet sizes be?

81dasher81
12-18-2012, 05:03 AM
i'd try a 155 and a 42.. the 42 just makes it start easier in the cold, and controls the idle, the main controls the amount of fuel over 1/3 throttle

400exrider21
12-18-2012, 02:37 PM
why is there such a small jet in there now though? 118???

kt1148
12-18-2012, 09:08 PM
it's more than likely a 148, not a 118. Look a little closer...stock is 148/38

400exrider21
12-19-2012, 06:43 AM
thats what i thought to and its a 118 cus a while back b4 the mods i replaced it with a 148 and it ran like shi* then i cleaned the old jet and it was a 118 so i replaced it with a 118 and it ran perfect but not it needs rejeting