Features: 1.Durable Material: The automatic clutch is made of premium aluminium alloy material, durable and reliable, rust and wear resistant, having a long service time. 2.Ideal Replacement: The engine start clutch is a perfect replacement for car repairing, can directly replace the old and broken accessory, ensuring the normal operation of your bike. 3.Easy to Install: The engine automatic clutch has a simple installation, convenient and time saving, don't need too much tools or complicated steps. 4.Improved Performance: The engine start automatic clutch can provide the performance to respond quickly o increase the smoothness of starting acceleration and shifting. 5.Various Use: The motor engine cover is suitable for Chinese 50cc to 110cc automatic engines, for most common style 4 Stroke horizontal cylinder engines of dirt bikes, ATVs, super pocket bikes, mini choppers, go karts. Specification: Item Type: Automatic Clutch Outer Diameter: Approx. 102mm/4.0in Hole Diameter: Approx. 17mm/0.7in, Approx. 15mm/0.6in Screw Hole Distance: Approx. 55mm/2.2in Fitment: For Chinese 50cc-110cc Automatic Engines, For Most Common Style 4 Stroke Horizontal Cylinder Engines Found On Chinese Dirt Bikes, ATVs, Super Pocket Bikes, Mini Choppers, Go Kart.