Vortex 120BZK-37 CAT5 Aluminum Rear Sprocket 525 Pitch 37-Tooth Black

The Vortex 120BZK-37 is a CAT5 aluminum rear sprocket designed for 525-pitch chain drive systems. Featuring a 37-tooth count and a striking black anodized finish, this sprocket is built for riders who want a lightweight upgrade over heavy OEM steel sprockets without sacrificing durability or performance.

Key Features:

• 525 Chain Pitch — compatible with 525-series chain drive systems
• 37 Teeth — precision tooth count for optimized final drive ratio
• CAT5 Aluminum Construction — specially formulated alloy per Vortex specifications for maximum strength-to-weight ratio
• Black Anodized Finish — anodized first, then CNC machined, resulting in a durable finish with silver highlights on tooth faces
• 100% CNC Machined — precision manufactured to exact tolerances for consistent fit and performance
• Vortex Patented Tooth Design — unique saber-tooth groove profile increases sprocket longevity and promotes smooth chain engagement
• Reduced Rotating Mass — aluminum construction is significantly lighter than OEM steel, improving acceleration and throttle response

The 120BZK-37 is part of Vortex Racing's 120-series sprocket line, engineered to deliver race-proven performance for street and track applications. Replacing your stock steel sprocket with this aluminum unit reduces unsprung and rotating weight, contributing to sharper handling and improved drivetrain efficiency.