# 420 acting up! HELP!!!



## subforeman (Jan 2, 2010)

my brother-in-laws 420 has been acting up lately. when it gets warm, it will bog down really bad after you go past half throttle. it will idle fine but you cant give it a lot of gas or it will bog down (like its hitting a rev limiter). if you turn the bike off and let it sit for a little while, then crank it back up, it will run fine. it only runs bad after it gets warm. the plug fouled so i changed it and its still doing it. the plug looks real black. anybody know what to do or have any suggestions? this bike is completely stock by the way.


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## Polaris425 (Dec 16, 2004)

Sounds like jetting is off.


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## subforeman (Jan 2, 2010)

its fuel injected


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## byrd (Jul 14, 2009)

a 420 is bad about running rich and fouling plugs out. my old one never ran that way but i did foul out a few plugs b4 i added snorks and exhaust


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