I bought this bike a couple of years ago with 1900 miles on it and i am having problems with the way it runs.It seems that the front cylinder runs much hotter than the rear cousing my rear plugs to go bad in a hurry.Runs good at an idle, but under a load starts to run only on the front cylinder and flame comes out of the rear cylinder.out the tailpipe I took the bike to a mechanic and he put a new carb,jet kits,tested every thing .this has been going on for two years if you have any ideas it would be just great frank las vegas nv