Cylinder Piston Top End Kit for Yamaha Big Bear Kodiak 400 1993-12 4GB-11638-00

Cylinder Piston Top End Kit for Yamaha Big Bear Kodiak 400

This cylinder piston top end kit for Yamaha Big Bear and Kodiak 400 models references OEM 4GB-11638-00, supplying a replacement cylinder, piston, and gasket set for upper engine rebuilds.

Overview

This cylinder piston top end kit for Yamaha Big Bear and Kodiak 400 machines provides a matched cylinder, piston, and gasket set for upper engine service. The top end kit for Yamaha Big Bear 400 suits owners rebuilding a worn or scored top end at home. It references OEM 4GB-11638-00 for easy cross-checking against the original part number.

Built For Performance

• Cylinder and piston matched as a set for consistent clearance
• Gasket set seals base, head, and covers during assembly
• Cross-references OEM 4GB-11638-00
• Restores compression lost to ring and bore wear
• Complete upper end refresh in one kit

Fits These Machines

• for Yamaha Big Bear 400 1993-2012
• for Yamaha Kodiak 400 1993-2012

On-The-Job Use

• Rebuilding the top end on 400cc Yamaha ATV engines
• Replacing scored or out-of-spec cylinders
• Farm, trail, and utility riding where compression loss shows
• Scheduled engine refresh on high-hour machines

Specs At A Glance

Good To Know

Q: How do I confirm OEM 4GB-11638-00 matches my machine? A: Cross-check the number against your parts diagram or old cylinder before ordering. Serial number and model year can affect fitment.

Q: Can I install this kit without machining the cases? A: A matched cylinder and piston kit normally bolts on without case machining when the bore matches stock. Verify clearances and torque specs from your service manual.

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