Description
A worn or incorrect rear sprocket directly impacts your bike’s acceleration, top-end speed, and drivetrain efficiency—making sprocket selection critical for any serious rider. The JT Sprockets 39-tooth rear sprocket delivers the precise gearing you need with engineered strength that handles aggressive acceleration and sustained high RPMs without compromise. Built from premium C45 high-carbon steel and heat-treated for durability, this bolt-on replacement restores optimal power delivery while outlasting inferior alternatives.
- Fitment: Yamaha specific
- Tooth count: 39-tooth rear
- Material: C45 high-carbon steel
- Manufacturing: Computer-designed
- Surface finish: Bead blasted
- Heat treatment: Full hardening
- Installation: Bolt-on replacement
- Weight: Optimized minimum
- Quality standard: OEM-exceeding
- MPN: JTR848.39









