There are a lot of options if you do a search. You can clock the secondary clutch spring to help, change to different rollers, get a clutch kit, or have Airdam or Papa Slap machine your clutches. I'm not sure which is the best option for you, but others will chime in with some input.
-2011 Polaris RZR-4 800 (SOLD)
-1999 Polaris Sportsman 500 ATV
-2006 AC Prowler 650XT (SOLD)-- updated bevel gears, updated oil pump driven gear, 4 wheel disc brakes, line lock E-brake, Papa Slap clutch, Xentec HID's, Dynatek CDI, Warn skid plates, Intellitronix gauges, 2010 intake/cvt duct work and dust shield, RZR seats, Bestop folding windshield, full cab kit, rear cage and rear seats (4 seater)