Vortex 491AZK-51 Aluminum Rear Sprocket 520 Pitch 51-Tooth Black

The Vortex 491AZK-51 is a 51-tooth aluminum rear sprocket designed for motorcycles running a 520 pitch chain. Finished in an aggressive black anodize, this sprocket delivers the weight savings of lightweight aluminum construction without sacrificing the durability demanded by serious street and off-road riders.

Vortex sprockets are 100% CNC machined from high-grade aluminum billet and feature the brand's patented saber-tooth groove design, which reduces weight while maintaining structural integrity and extending sprocket life. The precision machining ensures consistent chain engagement and smooth power delivery lap after lap.

Key Features:

• 51-tooth rear sprocket for increased acceleration and low-end torque
• 520 pitch chain compatibility
• Black anodized aluminum construction for corrosion resistance and aggressive styling
• 100% CNC machined from lightweight aluminum billet
• Patented saber-tooth groove design reduces weight and increases longevity
• Precision tooth profile ensures smooth, consistent chain engagement
• Race-proven by world-class championship teams and riders

The Vortex 491AZK-51 is an ideal upgrade for riders looking to fine-tune their gearing for tighter tracks, trail riding, or any application where added low-end pull is desired. Manufactured in the USA to exacting tolerances, this sprocket is a direct bolt-on replacement.