Wiseco PK1704 GP Series Top End Piston Kit 2002-2025 Yamaha YZ250 YZ250X

Boost your bike's endurance and performance with the Wiseco GP Series Top End Kit. If your engine is struggling with power loss during sustained high-RPM riding, Moto-House MX provides this elite kit as the ultimate Racing Performance solution. Designed specifically for the Yamaha YZ250 and YZ250X, the PK1704 kit delivers the reliability needed for competitive 2-stroke racing while ensuring your top end is built to last.

The Wiseco GP Series features Heavy Duty forged construction, engineered and machined right in the USA. These pistons undergo extra lightening operations for enhanced throttle response and feature an Electra-Coated crown, ring grooves, and pin bores for maximum wear resistance. With the addition of ArmorGlide® skirt coating, this OEM Replacement protects against micro-welding, galling, and detonation, making it the premier choice for riders who demand the highest level of protection.

Top Features: Wiseco GP Series Top End Kit PK1704

• Forged in the USA: Precision-machined from high-tensile aluminum for superior strength compared to cast pistons.
• ArmorGlide® Skirt Coating: Reduces friction and protects the cylinder wall while preventing micro-welding at high temperatures.
• Electra-Coated Protection: Specialized coating on the crown and pin bores ensures maximum resistance to heat and wear.
• Enhanced Throttle Response: Lightened design allows for faster revving and improved power delivery across the RPM range.
• Comprehensive Rebuild Kit: Includes a 66.40mm piston, ring set, wrist pin, circlips, top-end bearing, and a complete gasket set.

Fitment List

Year Range	Vehicle Brand	Vehicle Model & Size
2002-2025	Yamaha	YZ250
2016-2025	Yamaha	YZ250X

Frequently Asked Questions

Q: What makes the GP Series different from a standard Wiseco piston?
A: The GP Series includes additional Electra-Coating and lightening operations specifically designed for the stresses of sustained high-RPM 2-stroke racing.

Q: Is the top-end bearing included in this kit?
A: Yes, the PK1704 kit is a complete solution and includes the high-quality wrist pin bearing alongside the gaskets and piston components.

Q: Will this fit my 2025 Yamaha YZ250?
A: Absolutely. This kit is updated for fitment on all YZ250 models from 2002 through the current 2025 model year.

Upgrade Your Ride and experience the difference 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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