2001 400ex.full white bro. exhaust. anyone have a clue to what a good jetting would be? also has k&n filter... thanks

 

I got the fmf power up jet kit when i did mine it said with exhaust filter and air box lid off do a 170 main and the needle on the 3rd clip my 2005 only had 1 clip on the needle so i had to buy the kit to get a new need plus now i have all the jets for where ever i ride

 

different brand jets are different sizes so dont go buy a stock jet that size.my dyno jets called for that size too they must be made by the same company.