WISECO Forged Piston for POLARIS SPORTSMAN 850, SPORTSMAN 850 EPS, SPORTSMAN 850 XP, SPORTSMAN 850 XPS 4X4 2009-2020

WISECO offers this piston kit for POLARIS SPORTSMAN 850, SPORTSMAN 850 EPS, SPORTSMAN 850 HIGH LIFTER EDITION, SPORTSMAN 850 XP, SPORTSMAN 850 XPS 4X4 2009-2020. The piston slides in the cylinder and takes the force of the air-fuel combustion, passing it to the connecting rod and crankshaft.

Why choose a forged piston?

Instead of simply being cast, a forged piston is hot-pressed under very high pressure and then machined: its metal is denser and free of air pockets.

• Stronger when hot: it copes better with high revs, overheating and detonation.
• Lighter for the same strength: less stress on the connecting rod and bearings.
• Good to know: depending on the alloy, it expands a little more and is fitted with more clearance; slight noise when cold is normal.
• Why does it cost more? Forging tools, full machining and surface treatments cost more than simple casting.

Why choose WISECO?

Wiseco has forged its pistons in Mentor (Ohio, USA) since 1941 and controls the whole process, from aluminium bar to the friction-reducing ArmorGlide skirt coating. Its pistons are developed with Team Honda HRC in Supercross (450 class since 2018).

When should you replace the piston on your POLARIS SPORTSMAN 850 EPS?

Harder starting, loss of power, blue smoke, oil consumption or a knock when cold: these are the signs of a tired top end.

No manufacturer hour figure for this model. Cross-Mania guideline: compression check every 50 h in hard use and every 100 h for leisure.

Specifications and fitting tips

• Material: Aluminium
• Piston compression: Standard
• Oversize Letter: A
• Forged piston Ø 87.00
• Compression : standard : 11.5:1
• Manufacturer part number: W40106M08700

Cross-Mania tip: Measure the cylinder bore before ordering: the piston must match your cylinder size. Follow the manufacturer's break-in procedure and replace the top-end gaskets at the same time.

Also needed with this part

• 4-stroke engine oil : LIQUI MOLY 10W40 1 L · MOTUL 10W50

Compatibility

Check the exact model and year of your bike in the list below before ordering.

Fits:
POLARIS SPORTSMAN 850 2020
POLARIS SPORTSMAN 850 2019
POLARIS SPORTSMAN 850 2015
POLARIS SPORTSMAN 850 2014
POLARIS SPORTSMAN 850 2013
POLARIS SPORTSMAN 850 EPS 2014
POLARIS SPORTSMAN 850 EPS 2013
POLARIS SPORTSMAN 850 EPS 2012
POLARIS SPORTSMAN 850 EPS 2011
POLARIS SPORTSMAN 850 EPS 2010
POLARIS SPORTSMAN 850 EPS 2009
POLARIS SPORTSMAN 850 FOREST 2014
POLARIS SPORTSMAN 850 FOREST 2013
POLARIS SPORTSMAN 850 FOREST 2012
POLARIS SPORTSMAN 850 HIGH LIFTER EDITION 2020
POLARIS SPORTSMAN 850 HIGH LIFTER EDITION 2019
POLARIS SPORTSMAN 850 HIGH LIFTER EDITION 2018
POLARIS SPORTSMAN 850 HIGH LIFTER EDITION 2017
POLARIS SPORTSMAN 850 HIGH LIFTER EDITION 2016
POLARIS SPORTSMAN 850 SP 2017
POLARIS SPORTSMAN 850 SP 2016
POLARIS SPORTSMAN 850 SP 2015
POLARIS SPORTSMAN 850 TOURING SP 2015
POLARIS SPORTSMAN 850 TOURING XP 2014
POLARIS SPORTSMAN 850 TOURING XP 2013
POLARIS SPORTSMAN 850 TOURING XP 2012
POLARIS SPORTSMAN 850 TOURING XP 2011
POLARIS SPORTSMAN 850 TOURING XP 2010
POLARIS SPORTSMAN 850 XP 2014
POLARIS SPORTSMAN 850 XP 2013
POLARIS SPORTSMAN 850 XP 2012
POLARIS SPORTSMAN 850 XP 2011
POLARIS SPORTSMAN 850 XP 2010
POLARIS SPORTSMAN 850 XP 2009
POLARIS SPORTSMAN 850 XP EPS 2014
POLARIS SPORTSMAN 850 XP EPS 2013
POLARIS SPORTSMAN 850 XP EPS 2012
POLARIS SPORTSMAN 850 XP EPS 2011
POLARIS SPORTSMAN 850 XP EPS 2010
POLARIS SPORTSMAN 850 XPS 4X4 2014
POLARIS SPORTSMAN 850 XPS 4X4 2013
POLARIS SPORTSMAN 850 XPS 4X4 2012
POLARIS SPORTSMAN 850 XPS 4X4 2011
POLARIS SPORTSMAN 850 XPS 4X4 2010
POLARIS SPORTSMAN 850 XPS 4X4 2009
POLARIS SPORTSMAN 850 XPS TRG 4X4 2013
POLARIS SPORTSMAN 850 XPS TRG 4X4 2012
POLARIS SPORTSMAN 850 XPS TRG 4X4 2011
POLARIS SPORTSMAN 850 XPS TRG 4X4 2010
POLARIS SPORTSMAN 850 XPS TRG 4X4 2009