200 main???

[RideRedEX]

i have a 300ex it is bored 305cc with a 11-1 piston a 236 web cam k&n filter fmf exhaust and a white brothers 32mm mikuni flat slide carb. the jets that were sent with the carb were a 180, 190 and 200 main, 20, 22.5 and a 25 pilot . It ran fine for a year with the 200 main and 25 pilot which was done by KTM. now its running real rich won't idle. i've tried about all the jets it came with and its still rich. should i go buy some smaller jets and what would cause it to run great for a year then just start turning to crap. i'm about ready to go back to the stock carb

[RideRedEX]

ok i just read on here that a 190 mikuni jet is the same as a 202 dynojet and something about a kehin jet is a step above a dynojet. this would make my mikuni equal to a like 205 kehin jet how is that possible?

[RideRedEX]

bump

u need to seriously rejet man. Whoever did that was an idiot. barely any 400s with engine work run a 200 and if they do they are running sumtin really really bored out. U need to go down to prolly a 140 prolly lower though.

[cals400ex]

he is using a mikuni carb, not a keihin. there numbering pattern is different but i still don't think you need that big. i know my friend runs a mikuni 170 in his piped z400 with the airbox lid off.