Wiseco SK1390 Pro-Lite 2-Stroke Top End Kit Polaris 440 IQ 66.00mm Standard Bore

The Wiseco SK1390 is a complete 2-stroke Pro-Lite top end kit engineered for the Polaris 440 IQ snowmobile (2005–2007) featuring a 66.00mm standard bore and 438cc displacement. This kit provides everything needed for a full top end rebuild in a single package, eliminating the need to source components separately.

What's Included:

• Forged Pro-Lite piston
• High-performance piston rings
• Alloy wrist pin
• Circlips
• Top end bearing
• Complete top end gasket kit

Pro-Lite Forged Piston Technology:

• Forged from high-silicon aluminum bar stock for greater strength and reduced thermal expansion at high temperatures
• CNC-machined to optimal cam shape and profile for peak horsepower and extended service life
• Electra Coated skirt finish reduces friction and improves wear resistance
• Condensed, aligned grain structure delivers superior resistance to impact and fatigue versus cast alternatives
• Optimized strength-to-weight ratio using aerospace-grade alloy

USA-Made Quality:

• Forged and machined entirely in-house at Wiseco's USA facility
• In-house dyno testing validates performance before release
• Full manufacturing control from raw bar stock to finished, coated part

Wiseco's SK top end kits are developed specifically for snowmobile applications and validated under the extreme conditions of snocross and cross-country racing. This kit restores lost compression and power to your Polaris Liberty 440 motor, bringing engine performance back to factory spec or beyond. Note: Wiseco rings are application-specific and must only be used with Wiseco pistons.