617M06640 Wiseco Std Piston Kit 66.40 mm for Kawasaki KX250 1992-2001

Piston Kit for Kawasaki KX250

This Wiseco standard bore piston kit for Kawasaki KX250 keeps the stock 66.40 mm bore size, cross-referenced under part number 617M06640, and restores compression and top-end power.

Overview

This Wiseco piston kit for Kawasaki KX250 is a standard bore top-end component sized at 66.40 mm and identified by part number 617M06640. It replaces a worn piston and ring assembly at the original bore, helping bring back lost compression and throttle response. It fits riders and mechanics servicing a 1992-2001 KX250 without overboring the cylinder.

Built For Performance

• Standard bore sizing at 66.40 mm to match the stock cylinder
• Forged piston construction for strength under high-rpm loads
• Kit includes piston, rings, wrist pin, and circlips
• Machined ring grooves for consistent ring seal and compression
• Cross-referenced under part number 617M06640

Fits These Machines

• for Kawasaki KX250 1992
• for Kawasaki KX250 1993
• for Kawasaki KX250 1994
• for Kawasaki KX250 1995
• for Kawasaki KX250 1996
• for Kawasaki KX250 1997
• for Kawasaki KX250 1998
• for Kawasaki KX250 1999
• for Kawasaki KX250 2000
• for Kawasaki KX250 2001

On-The-Job Use

• Top-end rebuilds at the original bore size
• Motocross and off-road race engine refresh
• Trail and practice bike maintenance
• Restoring compression on a high-hour engine

Specs At A Glance

Good To Know

Q: Can I install this without boring my cylinder? A: Yes, this standard bore piston is sized at 66.40 mm to match the original cylinder, though the bore should be checked and honed for proper clearance.

Q: What comes in the kit? A: The kit typically includes the piston, piston rings, wrist pin, and circlips needed for a complete top-end replacement.

Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.