Renthal TwinRing Rear Sprocket 50T Blue 520 Chain 2240-520-50GPBU

Rear sprocket durability directly impacts acceleration response and chain life—cheap alternatives wear out in half the time and cost you races. The Renthal TwinRing solves this with a hybrid construction that combines the weight savings of aluminum with the wear resistance of hardened steel, outlasting all-aluminum sprockets by 3x while staying lighter than solid steel. If you're serious about consistent performance lap after lap, this is the sprocket that delivers.

The TwinRing's dual-material design uses a high-strength Ultralight™ 7075 T-6 aluminum inner ring bonded permanently to an electro-less nickel-coated steel outer ring. This bonding process—where the steel ring is expanded at 200°C and fitted over the aluminum core—creates an inseparable connection that won't delaminate under load. The result is a sprocket that handles hard acceleration, side-impact forces from chain tension, and abrasive track conditions without compromise.

Self-cleaning mud grooves machined between each tooth prevent dirt and debris accumulation, which otherwise accelerates tooth wear and increases drag. Flat socket head screws add lateral strength during impacts while sitting flush enough to avoid chain guide contact. At just 1.90 lbs, you're shaving unsprung weight while gaining three times the longevity of traditional options.

• Tooth Count: 50T
• Chain Size: 520
• Color: Blue
• Weight: 1.90 lbs
• Inner Ring: Ultralight™ 7075 T-6 aluminum
• Outer Ring: Electro-less nickel-coated steel
• Bonding: Permanent thermal expansion
• Design: Self-cleaning mud grooves
• Hardware: Flat socket head screws
• Durability: 3x all-aluminum sprockets
• Part Number: 2240-520-50GPBU
• Fitment: Vehicle-specific verification required