400ex running rich?


hey i got a 2000 400ex and it seems to be running rich i got a dg pipe a 152 main and a 42 pilot, i removed the choke and drilled holes in the airbox lid. i still have the stock air filter, but im thinking about getting a uni filter soon which should help...i think any suggestions on what i should do. thanks

i just pulled the plug and this is what it looked like



Insted of the UNI, get the ProDesign (ProFlow) air filter setup. The filter is made by UNI, but it has an aluminum adapter and cage that will not bend (the UNI cages are plastic and the lip will bend over time and have to be tossed!). The cage is way less restrictive than the stock one so this will indeed lean you up some, but this isn't really the proper way to jet a carb.


ok i am pretty much a 400ex god 1 the 42 pilot jet is to big for a stock 400 go back 3 a 38 the main jet is fine thats what comes with with the slip on i had the same exhaust on my 01 and u should b good

well i removed the choke, so if i go back to the 38 pilot will it be hard to start?

i have a kx 100 and a buddy is wanting to trade me his 400ex that needs pistion and rings and tires i dnt know much bout the 400ex any advice

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