The Tongsheng TSDZ2B represents the natural evolution of the celebrated TSDZ2, fixing the major flaws of its predecessor while keeping the torque sensor that made its reputation. Unlike Bafang motors that use a cadence sensor, this motor actually measures the force you apply to the pedals to deliver natural assistance. This detailed installation guide will help you avoid the costly mistakes that 70% of amateur installers make.
TSDZ2B vs Other Motors: Why This Particular Choice
The mid-drive motor market is packed with options, but the TSDZ2B occupies a unique position. Tongsheng learned from the recurring problems of the original TSDZ2 to produce a more reliable motor, notably in terms of waterproofing and durability of the blue nylon gear that broke regularly.
TSDZ2B Technical Specifications
| Feature | TSDZ2B | Real Advantage |
|---|---|---|
| Available power | 350W or 500W | Choice according to your usage and local legality |
| Sensor type | Integrated torque sensor | Assistance proportional to your effort |
| Bottom bracket compatibility | BSA 68-73mm only | Standard on most bikes |
| Motor weight | 3.6 kg | Lighter than BBSHD (6kg) |
| Waterproofing | Improved IPX5 | Better rain resistance than old TSDZ2 |
| Approximate price | $400-500 with battery | Excellent value for money |
Important Point: The TSDZ2B fixes the major problem of the blue nylon gear that broke on the old model. However, it remains sensitive to controller overheating during prolonged climbs, especially with the 500W version.
Tools & Preparation: Don’t Underestimate This Step
TSDZ2B installation often fails due to insufficient preparation. Unlike hub kits that mount quickly, a mid-drive motor requires completely dismantling the bottom bracket. This operation requires specific tools and a rigorous method.
Complete List of Essential Tools
| Tool | Specific Use | Possible Alternative |
|---|---|---|
| M33 wrench (supplied) | Tightening motor fixing nut | None, proprietary tool |
| Crank puller | Remove existing cranks | Hammer and chisel (not recommended) |
| Bottom bracket tool | Remove old BSA bottom bracket | Adjustable wrench (risky) |
| Allen keys 4, 5, 6mm | Display mounting, speed sensor, accessories | Screwdrivers with hex bits |
| Torque wrench | Respect tightening torques | “Feel” tightening (not recommended) |
| Marine grease | Protection against corrosion and seizing | Standard bike grease |
Warning: The TSDZ2B requires a BSA threaded bottom bracket of 68-73mm. Absolutely check compatibility before purchase. Press-Fit or non-standard bottom brackets are not compatible without specific adapter.
Step-by-Step Installation: The Details That Make the Difference
TSDZ2B installation follows a logical process but several steps hide traps that can compromise the assembly. Forums are full of questions about motors that vibrate, make noise, or lose power due to avoidable errors during installation.
Step 1: Dismantling & Bike Preparation
Removing Existing Components
- Remove pedals: Watch rotation direction, left pedal unscrews clockwise
- Remove cranks: Use appropriate puller, never force with hammer
- Extract bottom bracket: Clean frame threads thoroughly
- Photograph existing wiring: Save time during reassembly
Critical Point: Frame Compatibility Check
- Measure available space: Motor must not touch chainstay
- Check chain alignment: Chainring must align with cassette
- Verify ground clearance: Motor adds about 5cm downward
Step 2: Installing the TSDZ2B Motor
Mounting in Bottom Bracket
- Apply grease: On threads and contact surfaces
- Insert motor: From right side of bike, push until stop
- Screw M33 nut: Use supplied wrench, minimum 40 Nm torque
- Install anti-rotation plate: Mounting on chainstay with M5 bolts
Chainring & Crank Installation
- Mount 42T chainring: Usually pre-installed, check tightening
- Install TSDZ2B cranks: 40 Nm tightening torque required
- Remount pedals: Don’t forget reverse thread for left pedal
Step 3: Display & Component Installation
VLCD5 or VLCD6 Display Mounting
- Positioning on handlebars: Accessible area without releasing grips
- Display orientation: Readable without turning head
- Brake lever mounting: If included in kit, replace existing levers
- Switch installation: Within right thumb reach
Display Wiring
- Routing along down tube: Avoid friction areas
- Motor connection: Waterproof connector must engage properly
- Securing with ties: Every 20cm to prevent vibrations
Step 4: Speed Sensor & Battery
Speed Sensor Installation
- Left chainstay mounting: Supplied bracket or plastic ties
- Magnet on spoke: Precise alignment with sensor
- Gap adjustment: Maximum 5mm between magnet and sensor
- Function test: Spin wheel, check speed display
Battery Mounting
- Bottle battery on down tube: Optimal position for balance
- Drilling if needed: 7mm drill bit if original holes unsuitable
- Rivet nut installation: Essential for solid mounting
- Motor connection: Respect polarity, red = +, black = –
Settings & First Use: Optimizing Performance
Once installation is complete, the TSDZ2B requires some adjustments to fully exploit its capabilities. The torque sensor must be calibrated correctly, otherwise you risk having erratic or insufficient assistance. This step is often neglected but greatly determines the riding experience.
Torque Sensor Calibration
Initial Calibration Procedure
- Starting position: Feet on ground, don’t touch pedals
- Display power on: Hold power button 3 seconds
- Automatic calibration: Display shows “CAL” then returns normal
- Assistance test: Pedal gently, assistance should trigger progressively
Pro Tip: If assistance doesn’t trigger or starts brutally, repeat calibration. The torque sensor is sensitive to residual mechanical stress.
Assistance Mode Configuration
| Mode | Approximate Power | Recommended Use |
|---|---|---|
| ECO | 25% of motor power | Long trips, maximize range |
| TOUR | 50% of motor power | Daily use, power/range balance |
| SPEED | 75% of motor power | Moderate climbs, headwind |
| TURBO | 100% of motor power | Steep climbs, heavy loads |
Common Problems & Proven Solutions
Even with careful installation, certain problems can occur with the TSDZ2B. The user community has identified recurring failures and developed effective solutions. Knowing these weak points will save you from frustrating breakdowns and expensive repairs.
Failure Diagnosis Table
| Symptom | Probable Cause | Solution |
|---|---|---|
| Brutal or absent assistance | Poorly calibrated torque sensor | Recalibrate with feet on ground at startup |
| Metallic noise in motor | Worn or broken blue gear | Blue gear replacement (20€ part) |
| Power loss on climbs | Controller overheating | Let cool down, avoid prolonged TURBO mode |
| Incorrect speed display | Misaligned speed sensor | Readjust magnet/sensor gap to 5mm max |
| Cranks loosening | Insufficient tightening torque | Re-tighten to 40 Nm + thread locker |
| Display turning off alone | Faulty connection or battery BMS | Check connections, reset BMS if necessary |
Preventive Maintenance Tips
- Monthly check: Bolt tightening, cable condition
- Regular cleaning: Avoid high-pressure jets on motor
- Winter storage: Battery at 60% charge, dry place
- Firmware updates: Check forums for latest versions
TSDZ2B Installed: Enjoy Your New E-Bike
Your TSDZ2B now transforms your bike into a high-performing and natural electric companion. This motor excels in progressive assistance and respecting your pedaling effort, unlike the all-or-nothing systems of some competitors.
The TSDZ2B rewards careful installation with thousands of kilometers of riding pleasure. Take care of bolt tightening and waterproofing, this motor will reward you a hundredfold.
