6S5-12121-00-00 Exhaust Valve for Yamaha FX SHO 1800 2008-2015

Exhaust Valve for Yamaha

This exhaust valve, referenced under OEM part number 6S5-12121-00-00, controls exhaust flow in the 1800 engine used across the Yamaha FX SHO wave runner line.

Overview

This exhaust valve is a direct-fit replacement component for the 1800 engine found in the Yamaha FX SHO. It manages exhaust gas timing and flow, helping the engine run cleanly and hold steady power on the water. The exhaust valve is made for riders maintaining or rebuilding their Yamaha FX SHO between the 2008 and 2015 seasons.

Built For Performance

• Direct-fit replacement for OEM part number 6S5-12121-00-00
• Built to withstand the high-heat demands of the 1800 exhaust system
• Precision-machined for reliable sealing and consistent valve action
• Engineered to keep exhaust timing stable across the RPM range
• Sized for the Yamaha FX SHO 1800 engine platform

Fits These Machines

• for Yamaha FX SHO 1800, 2008-2015

On-The-Job Use

• Routine top-end rebuilds on the 1800 engine
• Replacing a burned or sticking exhaust valve
• Restoring factory compression and exhaust flow after a rebuild

Specs At A Glance

Good To Know

Q: How many should I order for a full engine rebuild? A: The 1800 engine uses multiple exhaust valves, so order the quantity your rebuild calls for. Match each valve to the correct cylinder position during assembly.

Q: Can this exhaust valve be installed without machine work? A: It fits the standard 1800 exhaust valve seat and reinstalls in the original location. Have the valve seat inspected and the clearance checked before you run the engine.

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