520 Chain & Sprocket Conversion Kit. 520 Sprocket / Chain Conversion Kit. Kit includes: 520 Pitch - 39T Rear Sprocket, 16T Front Sprocket, 96 Link DID Japanese Roller Chain.Includes Shim Kit with instructions. Reduces un-sprung weight up to 3lbs. Lightweight Rear Aluminum Sprocket is hard anodized (black) for long life. This kit converts the stock 530 Pitch to 520. Economy Cycle has tested this kit for fit and performance - Simple bolt on kit - Includes shim kit.