WISECO Forged Piston for POLARIS OUTLAW 525, OUTLAW 525 IRC, OUTLAW 525 IRS and KTM EXC 520, EXC 525, XC 525 1999-2013

WISECO offers this piston kit for POLARIS OUTLAW 525, OUTLAW 525 IRC, OUTLAW 525 IRS, OUTLAW 525 RS 2X4, OUTLAW 525 S and KTM EXC 520, EXC 525, SX 520, SX 525, XC 525 1999-2013. 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?

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
• Piston type: Forged
• Rings Quantity: Set
• Stroke: 4T

Available in several sizes: choose the one that matches your cylinder (stamped size or measured bore).

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

• Top-end gasket kit : ATHENA P400270600021 · ATHENA S410270001019
• Spark plug : NGK 4339 · NGK 3478
• 2-stroke oil : MOTUL 10W50 · LIQUI MOLY 10W40 1 L
• Air filter : TECNIUM 5818 · TECNIUM 0809

Compatibility

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

Fits:
KTM EXC 520 2002
KTM EXC 520 2001
KTM EXC 520 2000
KTM EXC 520 1999
KTM EXC 525 2007
KTM EXC 525 2006
KTM EXC 525 2005
KTM EXC 525 2004
KTM EXC 525 2003
KTM SX 520 2002
KTM SX 520 2001
KTM SX 520 2000
KTM SX 525 2006
KTM SX 525 2005
KTM SX 525 2004
KTM SX 525 2003
KTM SX 525 SUPERMOTO 2005
KTM SX 525 SUPERMOTO 2004
KTM XC 525 2012
KTM XC 525 2011
KTM XC 525 2010
KTM XC 525 2009
KTM XC 525 2008
POLARIS OUTLAW 525 2013
POLARIS OUTLAW 525 2012
POLARIS OUTLAW 525 2011
POLARIS OUTLAW 525 2010
POLARIS OUTLAW 525 2009
POLARIS OUTLAW 525 2008
POLARIS OUTLAW 525 2007
POLARIS OUTLAW 525 IRC 2011
POLARIS OUTLAW 525 IRC 2010
POLARIS OUTLAW 525 IRC 2009
POLARIS OUTLAW 525 IRC 2008
POLARIS OUTLAW 525 IRC 2007
POLARIS OUTLAW 525 IRS 2013
POLARIS OUTLAW 525 IRS 2012
POLARIS OUTLAW 525 IRS 2011
POLARIS OUTLAW 525 IRS 2010
POLARIS OUTLAW 525 IRS 2009
POLARIS OUTLAW 525 IRS 2008
POLARIS OUTLAW 525 IRS 2007
POLARIS OUTLAW 525 IRS 2006
POLARIS OUTLAW 525 RS 2X4 2011
POLARIS OUTLAW 525 RS 2X4 2010
POLARIS OUTLAW 525 RS 2X4 2009
POLARIS OUTLAW 525 RS 2X4 2008
POLARIS OUTLAW 525 RS 2X4 2007
POLARIS OUTLAW 525 S 2011
POLARIS OUTLAW 525 S 2010
POLARIS OUTLAW 525 S 2009
POLARIS OUTLAW 525 S 2008
POLARIS OUTLAW 525 S 2007