CSC Go QMB139 right-side front brake master cylinder assembly showing integrated DOT fluid reservoir black ball-end lever banjo bolt output and two-wire brake light switch pigtail with green blue wires and bare spade terminals CSC Go QMB139 right-side front brake master cylinder assembly showing integrated DOT fluid reservoir black ball-end lever banjo bolt output and two-wire brake light switch pigtail with green blue wires and bare spade terminals
CSC Go QMB139 front brake master cylinder assembly opposite side view showing brake switch wiring exit and DOT warning label on reservoir cap CSC Go QMB139 front brake master cylinder assembly opposite side view showing brake switch wiring exit and DOT warning label on reservoir cap
CSC Go QMB139 right-side front brake master cylinder assembly showing integrated DOT fluid reservoir black ball-end lever banjo bolt output and two-wire brake light switch pigtail with green blue wires and bare spade terminals
CSC Go QMB139 front brake master cylinder assembly opposite side view showing brake switch wiring exit and DOT warning label on reservoir cap

Chicago Scooter Company

Front Brake Master Cylinder w/ Brake Switch - 50cc Scooters

SKU 1000-4038
$35.00
Shipping calculated at checkout.
Description

Restore full hydraulic front braking with this OEM right-side front brake master cylinder assembly for the CSC Go and QMB139-engine Chinese scooters equipped with hydraulic disc brakes. Black finish with integrated DOT fluid reservoir, ball-end brake lever, banjo bolt hydraulic output fitting, and two-wire brake light switch pigtail (green/blue wires, bare spade terminals).

Key Features

  • Complete Assembly: Master cylinder, integrated fluid reservoir, ball-end lever, and brake light switch included.
  • Integrated Brake Light Switch: Two-wire pigtail (green/blue) with bare spade terminals — plugs directly into factory harness.
  • Banjo Bolt Hydraulic Output: Standard fitting for hydraulic disc brake hose connection.
  • Right-Side Fitment: Front brake (right handlebar).

Specifications

  • SKU: 1000-4038
  • Side: Right (front brake)
  • Brake Type: Hydraulic disc
  • Reservoir: Integrated, with DOT warning label cap
  • Lever: Ball-end, black
  • Output Fitting: Banjo bolt
  • Switch: 2-wire brake light switch, green/blue pigtail, bare spade terminals

Compatibility

  • CSC Go (all versions with hydraulic front disc brake)
  • CSC Go MAX (hydraulic front disc brake)
  • QMB139-engine Chinese scooters with hydraulic front disc brake systems

 
Product Diagrams
Features
  • Complete Assembly — Master Cylinder, Integrated Reservoir, Ball-End Lever, and Brake Light Switch
  • Integrated 2-Wire Brake Light Switch — Green/Blue Pigtail, Bare Spade Terminals
  • Banjo Bolt Hydraulic Output Fitting for Disc Brake Hose
  • Right-Side Fitment (Front Brake)
  • OEM Direct Replacement for CSC Go and QMB139 Hydraulic Disc Brake Systems
Specifications

SKU: 1000-4038 | Side: Right (front brake) | Brake: Hydraulic disc | Reservoir: Integrated with DOT cap | Lever: Ball-end black | Output: Banjo bolt | Switch: 2-wire green/blue pigtail, bare spade terminals
Model Fitments

CSC Go (all versions with hydraulic front disc brake) | CSC Go MAX | QMB139-engine Chinese scooters with hydraulic front disc brake
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  • 30-day return period on eligible items
  • Flat-rate shipping for orders shipped to the 48 Contiguous United States.
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