Naraku red anodized CNC machined performance variator drive face for GY6 50cc 139QMB showing serrated outer edge, concentric machined rings, 26-spline center hub, and NARAKU PERFORMANCE engraving against black racing-spec packaging Naraku red anodized CNC machined performance variator drive face for GY6 50cc 139QMB showing serrated outer edge, concentric machined rings, 26-spline center hub, and NARAKU PERFORMANCE engraving against black racing-spec packaging
Naraku red anodized CNC machined performance variator drive face for GY6 50cc 139QMB showing serrated outer edge, concentric machined rings, 26-spline center hub, and NARAKU PERFORMANCE engraving against black racing-spec packaging

Naraku

Naraku Performance Variator Drive Face: 139QMB / GY6 50

SKU 137-29
$70.00
Shipping calculated at checkout.
Description

Eliminate belt slip and improve throttle response with the Naraku CNC Machined Performance Variator Drive Face. Engineered specifically for the 50cc QMB139 (GY6) engine platform, this red anodized aluminum drive face is precision-machined to ensure a perfectly flat contact surface, maximizing belt grip and efficiency throughout the entire RPM range. A direct upgrade over the stock cast face, which develops grooves over time that kill top speed and gear ratio transitions.

Model Compatibility

Fits the 139QMB / QMB139 engine family found in most 50cc 4-stroke Chinese scooters:

  • Engine codes: 139QMB | 1P39QMB | 139QMA
  • Brands: TaoTao, Wolf, Ice Bear, Bintelli, Kymco, SYM, and other GY6 50cc platforms

Key Features

  • CNC Machined Surface: High-precision finish optimizes the belt's contact patch, reducing friction-based heat and preventing belt slip.
  • Red Anodized Finish: Specialized anodizing improves heat dissipation, extending the life of your drive belt and variator rollers.
  • 26-Spline Center Hub: Manufactured to exact OEM tolerances for a rock-solid crankshaft connection.
  • OEM Component Compatible: Works with stock electric start, kick start components, and factory plastic cooling fan.

Technical Specifications

  • Material: CNC machined aluminum
  • Finish: Red anodized
  • Spline Count: 26
  • SKU: 137-29 | MPN: NK900.59

Mechanic's Note: The drive face is the outer half of your CVT pulley system. Over time, the stock face develops grooves from the belt that kill top speed — replacing it with this Naraku unit restores original gear ratio transitions. Note: Does NOT include the kick start gear or cooling fan — swap those over from your old unit during installation.

California Prop 65 Warning: www.p65warnings.ca.gov
Product Diagrams
Features
  • CNC machined surface eliminates belt slip and optimizes contact patch
  • Red anodized finish improves heat dissipation for longer belt and roller life
  • 26-spline center hub to OEM tolerances for solid crankshaft connection
  • Compatible with stock electric start, kick start, and factory cooling fan
  • Direct upgrade over grooved stock face — restores original gear ratio transitions
Specifications

Material: CNC machined aluminum | Finish: Red anodized | Splines: 26 | SKU: 137-29 | MPN: NK900.59 | Fitment: 139QMB / 1P39QMB / 139QMA GY6 50cc
Model Fitments

GY6 50cc 4-stroke engines: 139QMB, 1P39QMB, 139QMA; TaoTao, Wolf, Ice Bear, Bintelli, Kymco, SYM and other QMB139-platform scooters
  • Same day shipping for orders placed before 2PM (CST) M-F
  • 30-day return period on eligible items
  • Flat-rate shipping for orders shipped to the 48 Contiguous United States.
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