393M06600 Wiseco Piston Kit .080 for Yamaha RD350 RD400 1973-1979 66.00mm

Wiseco .080 Piston Kit for Yamaha RD350 & RD400

This Wiseco 0.080 inch oversize piston kit, reference 393M06600, is a 66.00 mm bore piston assembly for the Yamaha RD350 and RD400 two-stroke twins built from 1973 through 1979.

Overview

This Wiseco .080 Piston Kit for Yamaha RD350 and RD400 brings worn or damaged cylinders back to spec after an overbore. Each Wiseco piston kit for Yamaha RD350 and RD400 measures 66.00 mm, letting a machinist clean up scoring and taper during a top end rebuild. Riders and shops working on tired RD two-strokes get a forged Wiseco piston kit for Yamaha RD350 and RD400 made for the extra displacement.

Built For Performance

• Forged aluminum construction for added strength under combustion pressure
• 0.080 inch oversize bore size of 66.00 mm
• Wiseco 393M06600 series piston for the RD350 and RD400 engine
• Built for two-stroke engines turning high rpm
• Intended for cylinders machined to match the oversize bore

Fits These Machines

• for Yamaha RD350 1973-1979
• for Yamaha RD400 1975-1979

On-The-Job Use

• Top end rebuilds where the cylinder needs an overbore
• Repairing scored or worn RD350 and RD400 cylinders
• Vintage motorcycle restoration projects
• Two-stroke engine rebuilds at a machine shop

Specs At A Glance

Good To Know

Q: Does this piston drop into a stock cylinder? A: No, the .080 inch oversize piston requires the cylinder to be bored and honed to 66.00 mm before installation.

Q: How do I know if I need this oversize instead of a standard piston? A: Have the cylinder measured by a machinist, since scoring, taper, or wear beyond standard spec is what calls for an oversize piston.

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