Hi I have a 00 400ex that only runs while on choke & at high rpm's . It will ride around perfect at higher rpm's but when allowed to drop a little it begins to backfire then shuts off when allowed to drop lower on the rpms. Also I go threw plugs like crazy. Any help will be greatly appreciated.

Thank you

 

You have a plugged up pilot jet. Take the carb apart and give it a good cleaning. Make sure you REALLY clean the pilot and main jet.

 

ok I will try that. does that have to do with the plugs fouling to?

Thank you btw

 

If the plug is fuel fowled it can if you run it on the choke a lot. If it's oil fowled, then no.