upgrades

What Upgrades do you have for your atv's and what is recommened for a 2006 Sportsman 500 if i want more power... i just recently bought a new CDI for my ArcticCat but looking for upgrading the polaris.....

and where can you find upgrades for polaris??
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2006 Polaris Sportsman 500 4x4
Green/Black



2006 Arctic Cat 650 V2 4x4
LE Tony Stewart edition
Orange/Black
Swamp Fox Tires

The only place I know that sells aftermarket parts for a 500 would be Highlifter.I know there are prob more places than that but I know they sell parts for them.