WSM 50-220-04K Piston Kit 0.25mm Oversize 86.25mm Bore Honda 400

The WSM 50-220-04K is a +0.25mm oversize piston kit engineered for Honda 400 engines, bringing the bore diameter to 86.25mm. Manufactured in Germany, this kit is built to meet or exceed OEM quality standards, making it the ideal solution for engine rebuilds requiring a first oversize bore.

Key Features:

• Oversize Bore: +0.25mm over standard, resulting in an 86.25mm bore diameter
• MOS2 Coating: Skirts feature a non-abrasive, expansion-retarding molybdenum disulfide (MOS2) coating that reduces heat and friction, drawing heat through the piston walls and out the bottom for improved power and longevity
• Forged Construction: Competitively forged pistons deliver superior strength and durability over cast alternatives
• Improved E-Clip Design: Updated clip retention for more reliable piston pin retention during operation
• Complete Kit: Includes piston, ring set, wrist pin, and circlips — everything needed for a proper cylinder rebuild
• Made in Germany: Precision-manufactured to tight tolerances for consistent, reliable performance

Additional oversize rings are available separately for future rebuilds. Order one kit per cylinder. OEM Cross-Reference: 13101-HM7-000.