Tongsheng TSDZ2B Torque-Sensor Mid-Drive Kit (36V 250W / 48V 500W)

Tongsheng TSDZ2B bottom-bracket mid-drive with built-in torque and speed sensing; 250W/36V for EU pedelecs or 500W/48V where allowed.

Torque + speed sensor built into the motor for natural pedal assist
36V 250W (80 N·m) and 48V 500W (100 N·m) versions; 350W option
About 3.5–3.6 kg with controller integrated
Fits JIS bottom brackets 68 / 73 mm
Compact 42T chainring setup, thumb throttle and speed sensor included

The TSDZ2B is Tongsheng’s updated TSDZ2 conversion motor. The torque sensor in the spindle measures pedal force, so assistance builds up naturally as the rider pushes — a feel many customers prefer over cadence-only kits at a similar price point.

The 36V 250W version is aimed at EU pedelec builds, while the 48V 500W version suits markets that allow more power. Both install through a standard JIS bottom bracket and keep the bike’s own drivetrain.

Specifications

Parameter	Value
Motor	Tongsheng TSDZ2B
Motor weight	3.6 kg
Motor dimensions	134 × 156 × 182 mm
Pedal sensor	Speed + torque
Controller	Integrated in motor
Display	Selectable: 860C / EKD01 / other Tongsheng-protocol displays
Throttle	Thumb
Certifications	CE / EN15194 / RoHS
Brake compatibility	Rim / Mechanical disc / Hydraulic disc
Battery compatibility	36V or 48V Li-ion matching the motor version; max input 54.6V (not for 58.4V packs)

Models & specifications

Variant	Voltage
36V 250W (80 N·m)	36 V
48V 500W (100 N·m)	48 V
350W option	36 / 48 V

What’s in the box

TSDZ2B motor with integrated controller and torque sensor
42T chainring with chain guard (pre-installed)
Left and right crank arms
Thumb throttle
Speed sensor with magnet
1T4 cable
3 × spacer washers and mounting screws
BB lock wrench
User manual and cable ties

Highlights

Spindle torque sensor: Measures rider force on both pedals; assist ratio 36–300% per Tongsheng.
Updated clutch: The B revision uses a revised free-wheel clutch and reduction gearing.
Reduction ratio: 41:1 according to Tongsheng.
Light output: Supports e-bike lights from the display (rating differs by source).

FAQ

Is there an EU-legal version?

Yes, the 36V 250W version; it can be limited to 25 km/h through the display.

Does it fit a 100 mm fat-bike BB?

No. Tongsheng specifies 68 or 73 mm bottom brackets for the TSDZ2B.

Wholesale, quote-only. Tell us your quantity, target market and required configuration (voltage, display, wheel size / BB width) and we will reply with a quotation.