Pro Circuit type 496 jetting

[NorCal Patriot]

Im adding a pro circuit type 496 slip-on silencer with K&n airfilter (running no lid) to my 2003 400ex quad. I talked to PC and asked them for their jetting recommendations and they gave the following:

158 main
58 pilot
no adj. to stock needle settings
no adj. to stock air mixture screw

Im in the San Fran. bay area California.. seemed a little rich to me right off the bat..

anyone else running a similar setup that can recommend or share their settings/experiences? Thanks in advance..

[cals400ex]

that pilot seems a tad big. :eek2:

most people run around a 42 pilot with good luck. i also would run a 155-158 keihin mainjet. in the hot months, you would use smaller jets than in the colder months.