What do you think about these jetts?

[Dizing400ex]

I have an 06 400ex

Air box lid removed, KN w/outwear, spark arrestor removed, WB CDI rev box, one heat range colder plug, Sparks timing advance...

Im at about 2500 feet, im running a 160 main jet with needle on middle(3rd) groove... air/fuel screw is 3.5 turns out...

I had a 165 in with this setting and it was runnin pretty rich. In end of 4th into 5th a 400ex with stock intake, timing advance and CDI box, arrestor removed and with a heavier rider was pullin on me hard in 5th.... I switched to 160 and havent run him yet.. btw, he hasnt jetted at all...

what do you think??

im thinking i may play with the air fuel screw, ill do a plug check but i dont think i should have to go to 155 main....

[400exstud]

160 sounds close or even a little rich. Do you have the spark arrester removed from the stock pipe?

[hawaiiansupaman]

160 was a little rich for me with a full exhaust but try the plug check and go from there

[Dizing400ex]

Based on that, i may be going to a 155 main

Yes i have the spark arrestor removed from the stock pipe.

thanks for the replies so far.

Dustin

[patches85]

I got a question,in his list of mods he says he has the timing advance key and a rev box. I thought you couldn't use both?

[Dizing400ex]

Umm, i use both and i felt good throttle response difference from both things. I first had the CDI box installed and felt difference and then i installed the timing advance with good response too....

Ive never heard of this, although, please let me know what you hear that could make me take one off?? Overheating or what?

[patches85]

I just thought I read that somewhere in here.Maybe I'm wrong. I thought that the rev box advances the spark.