Kyosho V1S/QRC 2 Speed 43T RC Spur Gear - 39721-1

The Kyosho 39721-1 is a 43-tooth spur gear designed for the 2-speed gearbox fitted to the Kyosho V1S and Kyosho QRC radio control cars. Carrying the style code KYO39721-1, this is a direct factory replacement for the spur gear in the transmission assembly, restoring correct gear mesh and drivetrain performance when the original part becomes worn or damaged. If you're running a V1S or QRC and experiencing drivetrain noise, slipping, or stripped teeth, this is the part to reach for.

Key Features

• 43-tooth spur gear sized specifically for the Kyosho 2-speed gearbox used in the V1S and QRC
• Direct OEM replacement — no modification required to fit the existing gearbox housing
• Restores correct gear mesh ratio within the 2-speed transmission assembly
• Made to Kyosho factory specification, ensuring compatibility with the surrounding drivetrain components

Compatible With

• Kyosho V1S
• Kyosho QRC

What's Included

• 1x Kyosho 43T spur gear (KYO39721-1)