FRONT SPROCKET: 4054 KM teeth number : 15 Racing Sprocket with lightening holes REAR SPROCKET: 2152 C teeth number: 46 Rear sprocket C45 steel CHAIN: 520GXW plates number: 108 The leading edge XW-Ring seal is made of an advanced nitrile butadiene composite and features six contact lips and two convex inner/outer stabilizers. This means four lubrication pools to protect against high-speed abrasion, heat build up, torsional flex and the loss of lubricant under these extreme conditions. As a result GWX chains provide the user with 10 times longer wearlife compared to standard chains