Moto-Master 1212-1499 14T Front Countershaft Sprocket for Yamaha YZ85 — Hardened Steel 428 Chain

Moto-Master — Elite Core Power Delivery and Hardened Steel Armor for Motocross Racing Mini-Cycles

The most common cause of sudden engine-to-wheel power drop on the track is rapid wear and grooving on the countershaft sprocket from high-RPM mini-cycle acceleration. Standard front gears suffer from a "durability gap," where extreme torque loads from aggressive clutch drops cause teeth to warp, misaligning the drive chain and increasing frictional drag on the engine. The Moto-Master 1212-1499 Front Countershaft Sprocket solves this drivetrain fatigue pain point for youth racing pilots by utilizing premium, top-grade hardened steel engineered to manage continuous high-RPM stress without losing its flawless geometric profile.

This isn't an ordinary front drive gear; it is a weight-optimized racing component engineered for seamless System Synergy with your mini-bike's transmission output shaft and final drive loop. Formed via precision machining with zero grinding imperfections, this 14-tooth sprocket sports a natural steel finish built to resist heavy friction and surface galling under severe conditions. By preserving factory-accurate tooth geometry, it creates a Matched Performance interface with your drive chain, maximizing power transfer straight to the rear wheel while maintaining a true Factory Quality standard from the gate drop to the checkered flag.

• 1212-1499 (14 Tooth Front Countershaft Sprocket): A top-grade hardened steel front drive sprocket designed for 428 pitch configurations to deliver custom gearing setups on high-revving mini platforms.

• Top-Grade Hardened Steel Alloy: Crafted from industrial-strength premium steel that undergoes specialized heat treatment to ensure excellent core density and resistance to tooth wear.
• 428 Chain Size Optimization: Machine-cut to seamlessly interface with standard high-performance mini motocross 428 chains, eliminating tight links and rough rolling resistance.
• Concentric Precision Machining: Built to perfect geometric circular specs without stamping flaws, eliminating countershaft vibration and securing consistent case clearance.
• Debris Shedding Mud Grooves: Engineered with deep, clear relief channels that expel packed sand and clay instantly, stopping chain jumping during wet track conditions.
• High-RPM Stability: Hardened spline pathways lock firmly onto the Yamaha countershaft with minimal tolerance play, protecting output shaft splines from expensive stripping.

Moto-House MX Pro Tip:

When swapping out your mini-racer's countershaft sprocket, always double-check the wear on the rest of the drivetrain assembly. To secure a high-level Matched Performance and shield your fresh steel gear from accelerated rounding, never wrap an old, loose chain around a brand-new sprocket. We strongly advise replacing the front gear, rear sprocket, and a high-tensile 428 drive chain at the same exact time. Clean the countershaft splines completely, apply a light coat of grease, and ensure a new factory lock washer or snap ring is correctly crimped into place.

Year	Make	Model
2002 - 2025	Yamaha	YZ85
2022 - 2025	Yamaha	YZ85 LW (Large Wheel)

FAQ Questions

Q) Will a 14-tooth front sprocket provide my YZ85 with more acceleration or higher top-end speed?
A) Going to a 14-tooth front sprocket (typically adding a tooth over stock) will increase your mini-cycle's top-end speed and smooth out the power delivery across long track sections, making it ideal for fast, open tracks.

Q) Does this countershaft sprocket require a specialized racing chain?
A) No, this sprocket is precisely cut to work with any high-performance 428-pitch non-sealed or sealed motocross racing chain standard to the Yamaha YZ85 platform.

Q) Does this kit include a replacement lock washer and countershaft nut?
A) No, this includes the individual 14-tooth hardened steel front sprocket only. We highly advise reusing your factory hardware or replacing the locking tabs with OEM parts if they show signs of bending stress.

Moto-House MX – Choice of Champions – is located in Clermont/Montverde, FL. We are the best motocross shop in Central Florida with lightning-fast shipping.