I have a 2000 400ex and I just bought an HMF Sport Series pipe. I don;t know what to jet it at though the website saids 180/200 but the local shop said thats really big. does any1 have thsi setup or know how to jet it. This would be really helpful

 

Get a Dial-A-Jet kit.

 

alot of times you dont even need to re-jet the carb....most of the time a turn of the air/fuel screw works perfect...does it bog real bad or blow out black smoke....?

 

not it doesnt bog or blow black smoke or anything. I bought a 152 jet today and put it in and it runs alot smother but it still backfires and pops when i was testing out thew new jet. I gave it gas till the point where you would **** then I let off and let it slow down thats when it was popping and backfiring. thanx for the advice ill try it

 

You will cure all your problems w/ this kit.........way better than re-jetting...but, now that you re-jetted, you'ld have to put your stock jet back in.

 

back firing and popping is a sign of a lean mixture but alot of bikes do this when you let off the gas (cars too) ...spark plug will tell you.....pull your plug, it will be light in color if its lean