Description
A worn or poorly designed front sprocket directly impacts your YZ85’s acceleration response, chain wear rate, and overall drivetrain efficiency. The Renthal 13-tooth sprocket eliminates these weak points with case-hardened construction and precision CNC machining that delivers consistent engagement and measurable weight savings. If you’re serious about sharpening your bike’s power delivery and extending component lifespan, this is the upgrade that separates competitive setups from stock builds.
Renthal’s engineering focuses on the details that matter: self-cleaning mud grooves that prevent debris accumulation in high-mud conditions, an ultralight design that shaves 10-15% off unsprung weight for snappier handling, and 655M13 nickel chromium steel that resists tooth wear even under aggressive riding. This is a bolt-on replacement that works seamlessly with your existing 428 chain and Yamaha YZ85 drivetrain—no modifications required.
- Part Number: 257–428-13GP
- Teeth: 13
- Material: Case-hardened 655M13 nickel chromium steel
- Chain Size: 428
- Weight: ~4 pounds
- Fitment: Yamaha YZ85 (2002–2026)
- Installation: Bolt-on
- Weight Reduction: 10-15%
- Mud Grooves: Self-cleaning machined
