2020-2022 YAMAHA YZ450F - OVERSIZE BIG VALVE KIT Tech Specs QTY (2) +1.5 mm Steel Exhaust Valve (32 mm) QTY (2) +2.0 mm Titanium Intake Valve (39 mm) These are sold as a complete set of QTY (4) oversize valves designed for the 2020-2022 Yamaha YZ450F MX engine. We are the ONLY ones offering valves like this! Once they are gone it will be another 12-18 weeks before we have more. Get them while you can. Huge power gains for the Yamaha YZ450's performance with this set of oversized valves. Manufactured in the USA and designed by us. Tailored for big bore setups and optimized for maximum power, these valves excel in drag racing and hill climb applications. With exceptional durability, these valves offer increased piston to valve clearance with reduced margin and weight! Maximized airflow thanks to their custom design featuring back cuts and special tulip shape.