STM ATV Tuner Torsion Upgrade

Description:

Upgrade and convert your Tuner ATV driven into an adjustable torsion spring driven. This has seven adjustable positions on the spring cover and two different spring rates to choose from. Includes hardware and a spanner tool for ease of installation. It will require drilling a 17/64 hole in the fixed sheave if you are adding this upgrade to your existing compression Tuner driven.