Wiseco 804M06640 Pro-Lite Piston Kit 1999-2025 Yamaha YZ250 YZ250X

Restore the snap and explosive power of your Yamaha engine with the Wiseco 804M06640 Pro-Lite Piston Kit. If your bike is feeling sluggish or losing compression, Moto-House MX provides this high-performance OEM Replacement to bring your motor back to life. Designed specifically for all-purpose 2-stroke riding, the Pro-Lite series is the industry standard for riders who demand a balance of durability, longevity, and increased horsepower.

Every Wiseco Pro-Lite piston is engineered, forged, and machined in the USA from 4032 aluminum alloy. This dedicated forging process ensures Racing Performance by optimizing the strength-to-weight ratio, while Heavy Duty construction allows it to withstand the rigors of professional motocross. With extra lightening operations included in the manufacturing process, this 66.40mm piston kit significantly enhances throttle response, allowing you to pull harder out of every corner.

Top Features: Wiseco 804M06640 Pro-Lite Piston Kit

• Forged in the USA: Precision-machined from 4032 aluminum alloy for superior structural integrity over cast alternatives.
• Pro-Lite Engineering: Features specialized lightening operations to reduce reciprocating mass and improve engine rev speeds.
• Strength-to-Weight Optimization: Dedicated forging design provides a piston that is both incredibly strong and exceptionally light.
• Complete 2-Stroke Rebuild: Includes the 66.40mm forged piston, high-quality rings, wrist pin, and circlips for a full top-end service.
• Versatile Performance: Built for everything from local motocross tracks to demanding GNCC-style off-road racing.

Fitment List

Year Range	Vehicle Brand	Vehicle Model & Size
1999-2025	Yamaha	YZ250 (All Editions)
2016-2025	Yamaha	YZ250X
2022-2025	Yamaha	YZ250 Monster Energy Racing Edition

Frequently Asked Questions

Q: Is the Pro-Lite piston better than the stock Yamaha piston?
A: Yes, Wiseco Pro-Lite pistons are forged rather than cast, offering significantly higher strength and better resistance to shattering under high-performance conditions.

Q: Does this kit include the top-end gaskets?
A: This specific kit (804M06640) includes the piston, rings, pin, and clips. For a complete rebuild, Moto-House MX recommends pairing this with a top-end gasket set.

Q: What is the bore size of this piston?
A: This is a 66.40mm piston, which is the standard bore size for the Yamaha YZ250 2-stroke engine.

Upgrade Your Ride and experience the reliability of Wiseco forged technology today!

Moto-House MX – Choice of Champions – is located in Clermont/Montverde, FL. The best motocross shop in Central Florida.

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