Vortex 921AZKV4-37 VTX Aluminum Rear Sprocket 37-Tooth Black Anodized

The Vortex 921AZKV4-37 is a lightweight aluminum rear sprocket featuring a 37-tooth configuration and a black anodized finish. Designed for performance-oriented street and track riders, this sprocket is 100% CNC manufactured in the USA from a specially formulated aluminum alloy per Vortex specifications, delivering the ideal balance of weight savings and durability.

The black anodized coating is applied before the sprocket teeth are cut, resulting in Vortex's signature two-tone machined appearance while also protecting the aluminum from oxidation and corrosion. Vortex's patented tooth profile is engineered to maximize sprocket longevity and ensure smooth, efficient power transfer through the drivetrain.

Key Features:

• 37-tooth aluminum rear sprocket
• Black anodized finish for corrosion resistance and aggressive styling
• 100% CNC machined in the USA from specially formulated aluminum alloy
• Reduced rotating mass for improved acceleration, deceleration, and handling response
• Patented Vortex tooth design for extended sprocket life
• Lightweight construction compared to OEM steel sprockets

Replacing a heavy OEM steel sprocket with this aluminum Vortex unit reduces unsprung and rotating mass, helping deliver crisper throttle response and more agile handling. Always replace the chain and front sprocket at the same time and ensure chain pitch compatibility before installation.