Renthal Ultralight Rear Sprocket 45T 520 Chain Honda Yamaha 404U-520-45P-HA

Reducing unsprung weight is one of the most direct ways to improve throttle response and corner speed on dirt bikes and sport bikes alike. The Renthal Ultralight 45T rear sprocket sheds 66% of the mass found in traditional steel designs without compromising durability, meaning faster acceleration and more responsive handling. Whether you're chasing lap times or pushing through technical terrain, this CNC-machined 7075-T6 aluminum sprocket delivers the precision fitment and self-cleaning performance that serious riders demand.

The self-cleaning mud grooves machined into each tooth are engineered to shed mud and debris in real time, preventing the buildup that leads to power loss and accelerated tooth wear. Pair that with the hard-anodized finish and you get a sprocket built to handle both the punishment of off-road riding and the demands of consistent track use. This is a straightforward bolt-on upgrade that requires no fabrication—bolt it on and feel the difference in your bike's responsiveness immediately.

• Tooth Count: 45T
• Chain Size: 520
• Material: 7075-T6 aluminum
• Weight: 0.86 lbs
• Finish: Hard-anodized
• Position: Rear
• Fitment: Honda, Yamaha
• Installation: Bolt-on