2010 Polaris Sportsman 850 Service Manual, Page 27Get this manual
MAINTENANCE 16Loosen the jam nut and turn the lash adjuster until the valve lash is correct17Set the intake and exhaust valve lash to specification21Repeat steps 16-1822Clean sealing surfaces of the cylinder head and valve cover23Inspect the condition of the valve cover bolt rubber isolatorsIf rubber has become hardened or cracked, replace them24Install new valve cover seal and install the valve coverTorque the cover bolts to specification
= In mmIntake Valve Clearance: .006 in(.15 mm)
=TIn mmExhaust Valve Clearance: .009 in(.23 mm) 18Hold adjuster and torque the jam nut using torque wrench w10 mm crow's foot adaptorVerify clearance is still correct after tightening the jam nutValve Cover Bolts: 89 inlbs(10 Nm) 25Install the upper right-hand frame support and torque the (4) mounting bolts to specification
Upper Right-Hand Frame Support Bolts: 36 ftlbs(49 Nm) 26Reassemble vehicle by reversing this procedureStart the engine to ensure proper valve adjustment was performed
Rocker Jam Nut: 71-89 inlbs(8-10 Nm) 19Turn the drive clutch counter-clockwise to rotate the cam sprocket 225 to the PTO (#2) Adjustment PositionPTO (#2) Adjustment Position