Wiseco 40078M07400 Forged Piston Kit Compression - 4-Stroke 74.00mm 13 1

The Wiseco 40078M07400 is a high-performance forged 4-stroke piston kit engineered for the Yamaha YFM250R Raptor and XT250 platforms. Featuring a 74.00mm standard bore and 13:1 compression ratio, this kit is purpose-built to deliver maximum power and reliability in demanding ATV and trail riding applications.

Key Features:

• Forged 2618 aluminum alloy construction — delivers a superior strength-to-weight ratio compared to cast pistons, with condensed grain structure aligned to the part's features for improved impact and fatigue resistance
• ArmorGlide skirt coating — reduces friction, quiets operation, and improves scuff resistance for extended piston life
• Dedicated application-specific forging — designed and optimized specifically for this engine for precise fitment and peak performance
• Complete kit — includes piston, rings, wrist pin, and circlips — everything needed to complete the rebuild in one box
• 74.00mm bore / 13:1 compression ratio — standard bore sizing for a direct replacement or performance upgrade
• 4-stroke, 2-ring design — reduces weight and friction while increasing power and throttle response
• Engineered, forged, and machined in the USA — manufactured at Wiseco's facility in Mentor, OH to the tightest tolerances

Wiseco is the only aftermarket piston manufacturer in the United States that produces pistons exclusively through the forging process, ensuring every piston meets the strength demands of high-performance motorsport use. In-house dyno testing and rigorous R&D back every design.