Vortex 120BZB-51 Black Steel 51-Tooth 520-Pitch Rear Sprocket

The Vortex 120BZB-51 is a 51-tooth, 520-pitch black steel rear sprocket engineered for motorcycle applications demanding maximum durability and long service life. Built by Vortex Racing — a U.S.-based manufacturer with decades of motorsport heritage — this sprocket delivers proven performance across street, track, and off-road use.

Constructed from high-grade carbon steel and finished with an electroplated satin black coating, the 120BZB-51 resists corrosion while maintaining a clean, aggressive appearance. The hardened teeth are designed to withstand extended mileage without sacrificing structural integrity, making this an ideal choice for riders who prioritize longevity over the lighter weight of aluminum alternatives.

Key Features:

• 51 teeth — adds low-end torque and improves acceleration response
• 520 chain pitch — compatible with standard and conversion 520 drivetrain setups
• Carbon steel construction — laser-cut for precision fitment and extended wear life
• Electroplated black finish — corrosion-resistant satin black coating
• Hardened teeth — case-hardened for durability under heavy load
• Lightening holes — drilled to reduce overall rotating mass where applicable
• 100% USA manufactured — made to Vortex Racing's tight tolerances

Vortex Racing sprockets are trusted by professional race teams worldwide across Motocross, Supercross, Road Racing, and Flat Track disciplines. The 120BZB-51 is a direct bolt-on replacement for compatible applications requiring a 520-pitch, 51-tooth rear sprocket with the added protection of a black hard-coat finish.