Complete chain kit with increased gear ratio. Front sprocket: 15t Rear aluminum sprocket: 50t Chain: DID 525 VX (reinforced X-ring, gold) The chain length is adjusted to the size of the sprockets. Always check the correct length before connecting the chain. APPLICATION: The 15/50 ratio drive used in 600 ccm motorbikes is a good choice for street stunt riding. It makes it easier to do wheelies and gives a better acceleration with a slight decrease in the maximum speed - this is the effect than many customers ask about. Recommended product!