The TSDZ2 has been the torque-sensor DIY champion since 2017. The new TSDZ8 brings more power and better cooling. Here's whether it's worth the upgrade.
Tongsheng's TSDZ2 built a cult following among DIY e-bike purists who wanted torque-sensor ride feel without paying OEM e-bike prices. For 7 years, it was the only real alternative to BAFANG's cadence-sensor motors. In 2024-2025, Tongsheng released the TSDZ8 ā a thoroughly redesigned motor that addresses nearly every complaint TSDZ2 owners had.
If you're shopping for a torque-sensor mid-drive in 2026, you're choosing between these two. The TSDZ2 is cheaper and has a deeper community knowledge base. The TSDZ8 is more powerful, runs cooler, and has a color display. This guide helps you decide which is right for your build.
Varstrom TSDZ2B 48V 500W Mid Drive Kit (Tongsheng OEM)
ā ā ā ā ā 4.4- Power500W
- Voltage48V
- Torque80 NĀ·m
- Price$349 - $449
Tongsheng TSDZ2B with a true torque sensor ā power responds to how hard you pedal, not just that you pedal. Game-changer for natural ride feel.
Varstrom 48V 750W TSDZ8 Mid Drive Kit (1056W Peak, Torque Sensor)
ā ā ā ā Ā½ 4.5- Power750W (1056W peak)
- Voltage48V
- Torque120 NĀ·m
- Price$429 - $549
The new TSDZ8 fixes everything the TSDZ2 lacked ā more torque (120 NĀ·m), more peak power (1056W), better cooling, and a color display. Best torque-sensor mid-drive value on Amazon.
TSDZ2 vs TSDZ8: What's New
| Spec | Varstrom TSDZ2B 48V 500W Mid Drive Kit (Tongsheng OEM) | Varstrom 48V 750W TSDZ8 Mid Drive Kit (1056W Peak, Torque Sensor) |
|---|---|---|
| Release Year | 2017 | 2024 (general availability 2025) |
| Nominal Wattage | 500W (also 250W/750W variants) | 750W (1056W peak) |
| Max Torque | 80 NĀ·m | 120 NĀ·m |
| Weight | 3.6 kg | 3.8 kg |
| Cooling | Passive (limited) | Improved thermal management |
| Display | VLCD5 (basic) | 850C color (modern) |
| Thermal Cutoff | Common on long climbs | Rare |
| Open-Source Firmware | Mature (OSF) | In development |
| Community Knowledge | 7 years of forum posts | Growing but newer |
| Replacement Parts | Widely available | Becoming available |
| Price | $349-429 | $429-549 |
The Verdict
For most buyers in 2026, the TSDZ8 is the better choice. It fixes the TSDZ2's biggest weakness (thermal cutoff on long climbs) while matching the BBS02's torque output. The 850C color display is also a meaningful upgrade over the TSDZ2's basic VLCD5. The $80-120 price premium over the TSDZ2 is worth it for the improved cooling alone ā thermal cutoff on a hot climb is genuinely dangerous if you're in traffic.
The TSDZ2 still makes sense for: (1) riders who want mature open-source firmware (the OSF project for TSDZ2 is excellent and adds torque sensor customization), (2) riders who only need 500W and want to save $100, or (3) riders building ultra-light road conversions where every 200g matters.
For everyone else, get the TSDZ8. It's the motor the TSDZ2 always wanted to be ā and it's our top torque-sensor mid-drive pick for 2026.