TEKTRO HD-E3940 E-Bike 4-Piston Hydraulic Disc Brake Set - OEM Bulk

Key Specifications

• Brand: TEKTRO
• Model: HD-E3940
• System Type: E-Bike 4-Piston Open System Hydraulic Disc Brake
• Caliper Architecture: 4-Piston Forged Aluminum Caliper
• Lever Design: Ergonomic 3-Finger Cast Aluminum Lever Blade with Integrated Reed Sensor Switch
• Sensor Switch Connection: Integrated Electronic Motor Power Cut-Off Cable (Standard E-Bike Connection)
• Fluid Type: Tektro High-Performance Non-Corrosive Mineral Oil
• Mount Standard: Post Mount (74mm)
• Color: Matte Black
• Pad Compatibility: Tektro High-Performance Metal Ceramic / Resin Pads
• Condition: 100% Authentic Brand New
• Packaging: OEM Bulk (Protective Polybag)

Why Choose Tektro HD-E3940 E-Bike Brakes?

1. High-Torque 4-Piston Stopping Leverage

Four-piston caliper construction dramatically increases pad contact area and clamping force compared to standard 2-piston brakes, ensuring short stopping distances for heavy e-bikes and cargo setups.

2. Integrated E-Bike Motor Safety Cut-Off

Each lever is equipped with a factory-installed electronic sensor cable that immediately cuts motor power when the brake lever is engaged, preventing motor drag and extending brake pad life.

3. Superior Heat Dissipation & Modulation

The open hydraulic system and high-capacity caliper volume efficiently dissipate heat during heavy, continuous braking—eliminating lever fade and pad glazing on long downhill rides.

Compatibility & Installation Notes

• Sensor Wiring: Compatible with most standard e-bike motor controllers requiring sensor-based motor cut-off (check connector pin type on your controller).
• Rotor Compatibility: Compatible with 160mm, 180mm, and 203mm rotors (rotors and post-mount adapters sold separately).
• Bleeding & Maintenance: Uses non-corrosive mineral oil for easy maintenance and environmentally safe servicing.

Frequently Asked Questions (FAQ)

Q: Does this brake set include motor cut-off sensor cables?
A: Yes! The levers feature integrated electronic power cut-off sensor cables designed specifically for e-bike motor controllers.

Q: Is this a 2-piston or 4-piston brake system?
A: The HD-E3940 is a heavy-duty 4-piston hydraulic system built for higher stopping demands on e-bikes.

Q: Is this authentic Tektro?
A: Yes, 100% genuine Tektro factory components sourced directly through authorized OEM supply channels.

Q: What is OEM bulk packaging?
A: Items ship in industrial protective polybags instead of retail display boxes to pass direct savings to you.

Q: Fast Domestic Shipping?
A: Yes, all orders ship directly from our US warehouse for quick delivery.