need help jetting on a 440ex

[onelow]

i have a 440 big bore with a stage two hotcam. my head is ported and polished im running a full yosh system. my engine builder put a 146 main which is way to lean for my motor. now my header is bright purple from the lean condition.i havent had a chance to check the plug. the needle is on the third clip and im wondering which size main should i go up to. its a dynojet kit im using. im running with my lid on at sea level. thanks for any help

[moto93]

I have about the same set-up as you and I'm running a 155 main, needle 1 up from the bottom, and a 42 pilot.

[Sandragggen]

I ran a 175 main jet in my IMS440, 700' above sea level in the summer.

JMiller

[3x440ex]

if you take your air box lid off you should be using about a 170-175........if you keep it on i would try a 165.

[onelow]

thanks guys im gonna give the 165 main a shot see how that works ttyl. thats after my quad comes back from my motor builder that left a rag in my crankcase. i didnt get my new clutch fast enough for the guy that did my motor to install it. so i was gonna put it in after break in. opened up my case and guess what i found. not a happy camper.

[onelow]

another picture

[3x440ex]

daham!!! that's screwed up:huh :huh

[onelow]

ya tell me about it and to top it all off he was running a 146 main in my worked motor. i dont know what the hell this guy was thinking. also now my oil pump is gone i think from rag pieces. my motor builder is coming back on monday from vaction i only put 2 hours on my fresh motor and i think it needs a complete tear down now thanks to him.

[TRX_Thumper]

sounds like time for a new mechanic...and seems like a 148 is stock on a 400.....

[onelow]

yes a 148 is stock first and last time going 2 this guy after he fixes it im done with him.