Vortex 491ZB-39 520-Pitch 39-Tooth Black Aluminum Rear Sprocket

The Vortex 491ZB-39 is a 39-tooth, 520-pitch aluminum rear sprocket finished in black with silver machined accents. Engineered for street and track use, it delivers the lightweight performance and precision that Vortex Racing is known for.

Constructed from 7075-T6 billet aluminum and 100% CNC machined in the USA, this sprocket is held to the tightest tolerances for true concentricity, smooth power transfer, and reduced drivetrain noise. The PTFE black hardcoat finish bonds directly to the aluminum, creating a durable, low-friction surface that resists wear far longer than standard anodizing.

Key Features:

• 100% CNC machined in the USA to precise tolerances
• 7075-T6 billet aluminum construction for maximum strength-to-weight ratio
• PTFE black hardcoat finish with contrasting silver machined accents
• Vortex patented saber-tooth groove design increases sprocket longevity
• Lightweight design reduces rotating mass for improved acceleration response
• 520 chain pitch
• 39 teeth

The Vortex 491ZB-39 is a direct upgrade over OEM sprockets, offering race-proven durability and the ability to fine-tune gear ratios for optimal street or track performance.