This one-piece spider shim has been successfully used by many savvy clutch tuners to increase belt grip at take-off on some of the recent Cat models*. Previous Arctic drive clutches had three of the .060” washers under the spider. Some 07-09* models now come with fewer shims (2 × .060, 1 × .030). These clutches with fewer shims are sensitive and sometimes engage higher even with less spring rate. By replacing the existing washers with this one-piece shim it moves the spider out slightly, so that the flyweight is “untucked” more at first engagement for better leverage, and increases belt grip on some high torque models and is a good improvement in belt life. * Some 2010 models have a different drive clutch, spider, and shims and different spacing may be required.