2010 Polaris Sportsman 850 Service Manual, Page 135Get this manual
ENGINE Camshaft Timing
Also refer to Camshaft Timing Quick Reference (page 5.39)1Rotate camshaft clockwise until pin (A) is facing UP (use wrench across the flats on the sprocket end)567Align two sprocket marks with valve cover gasket surfaceSlide sprocket onto camshaft, aligning slot in sprocket with pinScrew in the sprocket bolt finger tightSprocket bolt must be tightened fully after cam chain tensioner is installed2Verify TDC mark on flywheel is aligned with crankcase parting line8Verify flywheel TDC mark is still aligned (be sure the crankshaft has not rotated from TDC) and that sprocket marks are aligned with gasket surface (note that cam chain tensioner installation may change the alignment slightly)If marks are not aligned, remove sprocket bolt and correct alignment10Proceed to Cam Chain Tensioner Installation (page 5.38)