Discussion Starter · #1 ·
Hey guys I'm new to forums. I've read alot on here but just cant seem to find the specific one. I have a 2001 honda 400ex I put a 440 bore kit on with a lexx exhaust k&n filter and stock carburetor. Just reacently installed a stage 1 hot cam and It backfires at high rpms. What do you guys think the cause is for that. I know my carb has a 155 jet in it. I do have a 175 jet laying around if I should try that.