Electric Assist System
Assembly250W mid-drive system with a 36V 14Ah downtube battery, a torque-sensing controller, and a bar-mounted display, giving pedal assist to 25km/h. A full specification article for this item is being written. Meanwhile its bill of materials and connections are below.
Electric Assist System parts and their functions
6 top-level parts · 260 parts in total · full bill of materials below
| # | Part | Qty | What it does |
|---|---|---|---|
| 1 | Mid-Drive Motor 7 parts | 1× | 250W mid-drive unit |
| 2 | Battery Pack 6 parts | 1× | 36V 14Ah downtube pack |
| 3 | Motor Controller 5 parts | 1× | Torque-sensing controller |
| 4 | Display Unit | 1× | Bar-mounted display |
| 5 | Torque Sensor | 1× | Bottom-bracket strain sensor that measures pedal force to scale assist. |
| 6 | Motor Harness 3 parts | 1× | Wiring loom tying motor, battery, controller, display, and brake cutoffs together. |
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Bill of materials for Electric Assist System
6 top-level lines · 41 rows shown · 260 parts total · indented to 3 levels| # | Item / sub-assembly | Part no. | Qty/assy | Ext. qty | Parts | Type |
|---|---|---|---|---|---|---|
| 1 | Mid-Drive Motor 7 parts | cargo-bicycle-mid-drive-motor | 1× | 1 | 34 | assembly |
| 1.1 | Stator Assembly 3 parts | stator-assembly | 1× | 1 | 3 | assembly |
| 1.1.1 | Stator Core (laminations) | stator-core | 1× | 1 | · | part |
| 1.1.2 | Copper Winding | copper-winding | 1× | 1 | · | part |
| 1.1.3 | Slot Insulation | stator-insulation | 1× | 1 | · | part |
| 1.2 | Rotor Assembly 4 parts | rotor-assembly | 1× | 1 | 19 | assembly |
| 1.2.1 | Rotor Shaft | rotor-shaft | 1× | 1 | · | part |
| 1.2.2 | Rotor Core | rotor-core | 1× | 1 | · | part |
| 1.2.3 | Neodymium Magnet | neodymium-magnet | 16× | 16 | · | part |
| 1.2.4 | Ball Bearing | ball-bearing | 1× | 1 | · | part |
| 1.3 | Motor Housing | cargo-bicycle-motor-housing | 1× | 1 | · | part |
| 1.4 | Reduction Gear Set 3 parts | cargo-bicycle-reduction-gear | 1× | 1 | 3 | assembly |
| 1.4.1 | Motor Pinion Gear | cargo-bicycle-pinion-gear | 1× | 1 | · | part |
| 1.4.2 | Output Gear | cargo-bicycle-output-gear | 1× | 1 | · | part |
| 1.4.3 | One-Way Clutch | cargo-bicycle-one-way-clutch | 1× | 1 | · | part |
| 1.5 | Ball Bearing | ball-bearing | 3× | 3 | · | part |
| 1.6 | Hall Sensor | hall-sensor | 3× | 3 | · | part |
| 1.7 | Oil Seal | oil-seal | 2× | 2 | · | part |
| 2 | Battery Pack 6 parts | cargo-bicycle-battery-pack | 1× | 1 | 111 | assembly |
| 2.1 | Li-ion Cell, 18650 | li-cell-18650 | 40× | 40 | · | part |
| 2.2 | Cell Holder | cargo-bicycle-cell-holder | 1× | 1 | · | part |
| 2.3 | BMS Board 4 parts | cargo-bicycle-bms-board | 1× | 1 | 66 | assembly |
| 2.3.1 | Bare PCB | pcb-bare | 1× | 1 | · | part |
| 2.3.2 | Microcontroller | mcu | 1× | 1 | · | part |
| 2.3.3 | SMD Passive (R/C/L) | smd-passives | 60× | 60 | · | part |
| 2.3.4 | BMS Power MOSFET | cargo-bicycle-bms-mosfet | 4× | 4 | · | part |
| 2.4 | Battery Case | cargo-bicycle-battery-case | 1× | 1 | · | part |
| 2.5 | Battery Lock | cargo-bicycle-battery-lock | 1× | 1 | · | part |
| 2.6 | Connector | connector | 2× | 2 | · | part |
| 3 | Motor Controller 5 parts | cargo-bicycle-controller | 1× | 1 | 102 | assembly |
| 3.1 | Bare PCB | pcb-bare | 1× | 1 | · | part |
| 3.2 | Microcontroller | mcu | 1× | 1 | · | part |
| 3.3 | Controller MOSFET | cargo-bicycle-power-mosfet | 6× | 6 | · | part |
| 3.4 | SMD Passive (R/C/L) | smd-passives | 90× | 90 | · | part |
| 3.5 | Connector | connector | 4× | 4 | · | part |
| 4 | Display Unit | display-unit | 1× | 1 | · | part |
| 5 | Torque Sensor | cargo-bicycle-torque-sensor | 1× | 1 | · | part |
| 6 | Motor Harness 3 parts | cargo-bicycle-motor-harness | 1× | 1 | 11 | assembly |
| 6.1 | Wire Bundle | wire-bundle | 1× | 1 | · | part |
| 6.2 | Connector | connector | 8× | 8 | · | part |
| 6.3 | Brake Cutoff Switch | cargo-bicycle-brake-cutoff-switch | 2× | 2 | · | part |
Where the electric assist system is used
1 product across 1 domain contain it, directly or inside a sub-assemblyUsed in 1 assembly
Sourcing: possible vendors
Browse the supplier directory → Prices, MOQ, and lead times are algorithmic estimates, not quotes, and not claims about these companies. Company mappings are curated by keyword; est. price band $0.50–$100. How estimates work| Vendor | HQ | Specialty | MOQ | Lead time |
|---|---|---|---|---|
|
🇨🇳Foxconn
foxconn.com ↗
|
Shenzhen, CN | Electronics contract mfg | 1,000 pcs | 6–10 wks |
| flex.com ↗ | Singapore | Electronics contract mfg | 1,000 pcs | 6–10 wks |
| dixoninfo.com ↗ | Noida, IN | Electronics contract mfg | 1,000 pcs | 6–10 wks |
| bydelectronic.com ↗ | Shenzhen, CN | Electronics contract mfg | 1,000 pcs | 6–10 wks |
| venture.com.sg ↗ | Singapore | Electronics contract mfg | 1,000 pcs | 6–10 wks |