6S5-12121-00-00 Exhaust Valve for Yamaha CrossWave 1900 2026

Exhaust Valve for Yamaha

This exhaust valve, OEM cross-reference 6S5-12121-00-00, controls exhaust gas flow in the engine cylinder head of Yamaha personal watercraft.

Overview

This exhaust valve for Yamaha is a direct-fit replacement for the 6S5-12121-00-00 part number used across several four-stroke marine engines. The exhaust valve seals combustion gases during compression and opens at the right moment to release them, keeping your engine running cleanly and efficiently. It suits riders and mechanics servicing the Yamaha CrossWave 1900 for the 2026 model year.

Built For Performance

• Precision-ground valve face for a consistent combustion seal
• Heat-resistant alloy construction built to handle continuous exhaust temperatures
• Stem dimensions matched to the 6S5-12121-00-00 specification
• Designed for four-stroke marine engine cylinder heads
• Direct replacement for the original valve without modification

Fits These Machines

• for Yamaha CrossWave 1900, 2026

On-The-Job Use

• Top-end rebuilds on Yamaha CrossWave 1900 watercraft
• Valve replacement during routine engine service
• Cylinder head refurbishment after compression loss
• Maintenance for high-hour personal watercraft engines

Specs At A Glance

Good To Know

Q: How many exhaust valves does this fit? A: This listing covers one exhaust valve, so order the quantity your cylinder head requires. Confirm the count against your engine before purchase.

Q: Does this valve require lapping during installation? A: A light lap to the valve seat is standard practice for a proper seal. Have a qualified technician check clearance and seating after installation.

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