More questions...i just bought this 400ex and it runs good when on the gas but wont idle. talk to the guy that had it before me and he said it idled in the summer and that he thinks its bad gas...hard to believe. i have yet to take the carb off and clean it and put new gas in but he also said he never rejetted it. has full fmf exhaust with power bomb header and k and n filter. and should i be rejetting for summer vs winter or no? im use to having my 03 Arctic Cat F7 with efi so im not use to the whole jetting the carb scene.