Small but vital go-kart & miini bike part For proper throttle function Simple to install The throttle return spring for the Predator 224cc 6.6 HP engine is a small but vital part of your go-kart or mini bike’s control system At our already low sale price, you may want to order an extra spring as a spare. The throttle return spring for the Predator 224cc 6.6 HP engine is a small but vital part of your go-kart or mini bike’s control system. At our already low sale price, you may want to order an extra spring as a spare. Wire size: 0.03 mm Coil diameter: 5.80 mm Length: 112 mm (4-13/32″)