Geared rear hub motors with threaded freewheel mounting: the workhorse layout for city and
trekking e-bikes, keeping the rider’s gears while adding 200W to 1000W of assist. The range
spans compact 2.3 kg single-speed hubs up to the 5 kg GDR-19 for 1000W cargo and touring duty.
These are wholesale, quote-only motors. Tell us your frame’s rear dropout width, freewheel
speed count, target power and brake type and we’ll confirm the matching model and pricing.
Models & specifications
| Model | Voltage | Rated power | Reduction | Dropout | Freewheel | Wheel sizes | Weight | Top speed |
|---|
| GDR-05H | 24V/36V/48V | 200-250W | — | 125/130/135mm | 1s | 16”-28” | 2.8 kg | 25 km/h |
| GDR-08 | 36V/48V | 250-350W | 1:4.4 | 138mm | 6-7s | 16”-28” | 2.8 kg | 25-28 km/h |
| GDR-11 | 36V/48V | 250W | 1:6.3 | 120/135mm | 1s | 16”-28” | 2.3 kg | 25-28 km/h |
| GDR-15 | 24V/36V/48V | 250-500W | 1:5 | 138mm | 6-9s | 16”-28” | 3.7 kg | 25-40 km/h |
| GDR-19 | 36V/48V | 500-1000W | 1:5 | 140mm | 6-7s | 20”-28” | 5.0 kg | 25-45 km/h |
| GDR-21 | — | — | — | — | — | — | — | — (spec sheet on request) |
All models: IP54 waterproof rating, ≥78% efficiency, -20 °C to 45 °C operating range,
24/96h salt-spray tested, V-brake and disc-brake compatible.
Highlights
- Torque where it counts: gear reduction multiplies torque at the rear wheel for stop-and-go city traffic and loaded riding.
- Keeps your gears: threaded freewheel interface takes 1- to 9-speed blocks, so shifting works exactly as before.
- Wide dropout coverage: 120mm through 140mm options fit everything from compact folders to touring frames.
- Proven construction: IP54 sealing and 24/96h salt-spray testing across the range.
