SINET™ Bottom Bracket Torque Sensor – 68 mm

The SINET™ Bottom Bracket Torque Sensor provides smooth, proportional pedal assistance by measuring the rider’s pedaling force and cadence. Unlike a basic cadence sensor that only detects crank rotation, the torque sensor adjusts motor assistance in response to how hard the rider is pedaling.

This sensor is designed for bicycles and trikes with a 68 mm bottom bracket shell and requires a compatible square-taper crankset.

• Measures rider pedaling force and crank rotation
• Provides smooth, proportional pedal assistance
• Fits a 68 mm bottom bracket shell
• Requires square-taper crankarms
• Designed for current E-BikeKit SINET™ systems
• Includes a protective cable grommet
• Bottom bracket torque-sensor extension cable sold separately

Installation Notice: Installation requires removal of the existing bottom bracket and drilling a cable-routing hole in the bottom bracket shell. The included grommet must be installed in the drilled opening to protect the sensor cable from the frame.

For larger frames, upright trikes, and recumbents, additional cable length may be required. The SINET™ Torque Sensor Extension Cable is sold separately.

The SINET™ torque sensor measures force applied through the crankset while also detecting crank rotation. The SINET™ controller uses this information to regulate motor output according to the rider’s effort and the selected pedal-assist level.

This creates a more natural riding experience than cadence-only pedal assist:

• Light pedaling produces lighter motor assistance
• Stronger pedaling produces greater motor assistance
• Assistance responds progressively instead of switching on at a fixed output
• Low-speed starts and transitions between assist levels feel smoother

The exact assistance response depends on the selected LCD assist level, controller programming, gearing, rider input, and operating conditions.

• Bottom Bracket Shell Width: 68 mm
• Crank Interface: Square taper
• Crank Compatibility: Requires compatible square-taper crankarms
• Electrical Platform: Current E-BikeKit SINET™ system
• Frame Modification: A cable-routing hole must be drilled in the bottom bracket shell
• Cable Protection: Included grommet must be installed in the drilled opening

Important: Confirm the frame has a 68 mm bottom bracket shell and sufficient internal clearance before installation. This sensor is not intended for press-fit bottom brackets, external-bearing crank systems, one-piece cranks, oversized bottom bracket shells, or incompatible crank interfaces.

Compatible With:

• Current E-BikeKit SINET™ conversion systems
• Current E-BikeKit SINET™ complete trike systems
• 68 mm threaded bottom bracket shells
• Compatible square-taper cranksets and crankarms
• SINET™ integrated-controller systems
• SINET™ external-controller systems

Not Compatible With:

• Legacy E-BikeKit pedal-assist systems
• Legacy E-BikeKit controllers or wiring harnesses
• Cadence-only pedal-assist connections
• Press-fit bottom bracket systems
• External-bearing crank systems
• One-piece crank systems
• Third-party electrical systems unless compatibility has been confirmed

Matching connector appearance alone does not confirm electrical compatibility. Verify the complete system platform and mechanical fit before ordering.

• Platform: E-BikeKit SINET™
• Product Type: Bottom bracket torque and cadence sensor
• Bottom Bracket Fit: 68 mm
• Crank Interface: Square taper
• Pedal-Assist Function: Proportional torque-sensing assistance
• Cable Routing: Through drilled opening in bottom bracket shell
• Cable Grommet: Included
• Extension Cable: Sold separately
• Variants: None

• One SINET™ 68 mm bottom bracket torque sensor
• One protective cable-routing grommet

Not Included:

• Crankarms
• Crankset
• Bottom bracket tools
• Drill or drilling tools
• SINET™ Torque Sensor Extension Cable

• Disconnect and remove the battery before beginning installation.
• Confirm the frame uses a 68 mm threaded bottom bracket shell.
• Remove the existing crankarms and bottom bracket using the correct bicycle tools.
• Confirm the replacement crankarms use a compatible square-taper interface.
• Select a cable-routing location that avoids welds, frame joints, structural reinforcements, and interference with internal components.
• Drill the required cable-routing hole using proper tools and installation practices.
• Deburr the opening and install the included grommet before routing the sensor cable.
• Do not route the cable through an unprotected metal opening.
• Install and tighten the torque sensor according to the required bottom bracket orientation and torque specifications.
• Route the cable away from chainrings, crankarms, chains, steering components, tires, and sharp edges.
• Align connector arrows and pins before joining the plugs. Do not twist or force the connectors.
• After installation, verify correct crank clearance and proportional pedal-assist operation before returning the bicycle or trike to service.

Professional Installation Recommended: This installation requires bicycle drivetrain service and permanent modification of the frame. It should be completed by a qualified bicycle or electric-bike technician familiar with bottom bracket installation, cable routing, and frame modification.

The standard sensor cable may not provide sufficient routing length for every frame configuration. Larger bicycle frames, upright trikes, and recumbent trikes commonly require additional cable length.

The SINET™ Torque Sensor Extension Cable – 59 cm is available separately and provides additional reach for cleaner routing with less strain on the cable and connectors.

Add the SINET™ Torque Sensor Extension Cable to your order.

• Provides smoother, more natural pedal assistance than cadence-only sensing
• Measures both crank movement and rider effort
• Designed for current SINET™ integrated and external-controller systems
• Best suited for compatible 68 mm square-taper bottom bracket installations
• Extension cable available for trikes, recumbents, and larger frames
• Phone, text, and email technical support
• Fitment and installation guidance available from E-BikeKit technicians

Dealer Note: Confirm bottom bracket width, crank interface, system platform, cable-routing requirements, and installer capability before supplying this component.