This is my sportsman 850 2010 for xc and endurance racing.
A lot of mod for more reliability:
Front RZR 800s caliper and disc at rear
Front RZR 900 XP hub and caliper and disc for more brake power and allow 12 wheel
23/8r12 and 23/10r12 for lowered gravity center
Engine is stock for the moment. I have an powercommander auto-tune un stock, I search an used powercommander5 and an exhaust.
sportsman xp 850 2010
RZR 900 front brake, RZR 800s front brake at rear, 12" wheel