Vortex 251AZRV4-42 CAT5 Aluminum Rear Sprocket 520 Pitch 42T

The Vortex 251AZRV4-42 is a CAT5 billet aluminum rear sprocket featuring a 520 pitch and 42 teeth, designed for high-performance motorcycle applications. Machined from a specially formulated aluminum alloy to Vortex's exacting specifications, this sprocket delivers an optimal balance of strength and weight savings over stock steel units.

Key Features:

• 520 Pitch — compatible with 520 chain setups including OEM and conversion applications
• 42 Teeth — stock-equivalent tooth count for balanced acceleration and top-end performance
• Lightweight aluminum construction — significantly reduces rotating mass compared to OEM steel sprockets for improved throttle response
• CAT5 design — features Vortex's patented saber tooth groove profile and unique CNC-machined sweep pattern for extended sprocket longevity
• Color anodized finish — durable anodized surface with contrasting silver machine-cut highlights on teeth, sweeps, and grooves
• 100% CNC manufactured in the U.S.A. — machined to tight tolerances for precise fit and reliable performance
• Vortex patented sprocket design for superior chain engagement and reduced wear

Vortex Racing has been a trusted name in motorcycle racing components for road racing, motocross, supercross, and flat track for over 15 years. Each sprocket is manufactured domestically and tested with feedback from top professional race teams worldwide, making the 251AZRV4-42 a proven choice for both track and street riders seeking a performance upgrade.