Wossner 8241DB Piston Kit - KTM 65 SX Husqvarna TC65 Gas Gas MC 65 Size B

Wossner 8241DB Premium Forged 2-Stroke Piston Kit - Size B

Keep your young racer at the front of the pack with the Wossner 8241DB Piston Kit. Specifically engineered for the high-revving 65cc engines found in the KTM 65 SX, Husqvarna TC65, and Gas Gas MC 65, this Size B forged kit is the professional choice for restoring Factory Quality power in cylinders that have seen standard operational wear. At Moto-House MX, we know that mini-cycle engines are pushed to their absolute limits; Wossner’s aerospace-grade forged alloy provides the structural integrity needed to handle the high heat and extreme RPMs of competitive motocross.

Forged from aerospace-grade aluminum alloy, the 8241DB offers superior strength and thermal resistance compared to standard cast pistons. This kit features a permanent skirt coating to minimize internal friction and piston rock, resulting in a quieter engine and more consistent power delivery. This Size B piston (44.97mm) is designed for cylinders with a 45.01mm bore, providing the precise fitment required to compensate for natural cylinder wear and maintain optimal compression.

Top Features: Wossner 8241DB Piston Kit

• Size B (44.97mm): Precision-engineered for 45.01mm bores to restore factory-spec tolerances in cylinders with slight wear.
• Aerospace Forged Alloy: High-strength aluminum construction built to withstand the mechanical stress of high-RPM 65cc racing.
• Low-Friction Skirt Coating: Permanent coating reduces wear on cylinder walls and ensures a more efficient break-in period.
• Single-Ring Racing Design: Optimized for reduced drag and maximum high-RPM efficiency, a must for the 65cc class.
• Complete Assembly: Kit includes the forged piston, high-quality ring, wrist pin, and clips.

Expert Pro-Tip: In the 65cc class, the piston is a high-maintenance item. Size B is the preferred choice for a top-end refresh when your cylinder is still in good condition but has worn slightly beyond the ideal clearance for a Size A piston. When installing the 8241DB, always replace your small-end wrist pin bearing and check your power valve for smooth operation. Using a fresh top-end gasket kit is essential for maintaining the primary compression needed for that signature 65cc "hit."

Fitment List

Brand	Models	Year Range
KTM	65 SX	2009-2025
Husqvarna	TC65	2017-2025
Gas Gas	MC 65	2021-2025

Frequently Asked Questions

Q: What is the difference between Size A and Size B?
A: Size B (44.97mm) is 0.01mm larger than Size A. This slight increase is designed to compensate for the natural, microscopic wear that occurs on a cylinder wall over time, restoring the engine to original factory performance levels.

Q: Why is a forged piston better for my child's 65cc bike?
A: 65cc engines are often ridden at maximum RPM constantly. Forged pistons are much denser and stronger than cast pistons, providing a significant safety margin against cracking or shattering under the extreme loads of racing.

Q: Does this kit include the wrist pin bearing?
A: No, the kit includes the piston, ring, pin, and clips. We highly recommend purchasing a new high-quality small-end bearing separately for every top-end rebuild to ensure reliability.

Recommended Pairings

• Top End Gasket Kit: Essential for a professional, leak-free engine rebuild with a fresh set of gaskets.
• Motorex Cross Power 2T Oil: Premium synthetic protection specifically formulated for high-performance 2-stroke race engines.

Restore your machine’s power and precision today. Buy now at Moto-House MX!

Moto-House MX – Choice of Champions – is located in Clermont/Montverde, FL. The Best Motocross/UTV & ATV Shop in Central Florida. Stop by our local store in Montverde, FL or enjoy lightning-fast shipping across the USA.