Fitted a new motor or controller and it stutters, grinds, or refuses to turn? The wiring is almost certainly out of sequence. There are 36 possible combinations of three phase wires and three hall wires. One or two of them work. Here is how to find them without guessing blindly.
Disconnect the battery every single time you change a connection. Unplugging phase wires under power arcs across the contacts and destroys controller MOSFETs.
What comes out of the motor
A standard hub motor has eight or nine wires:
- Three thick phase wires — yellow, green, blue. These carry the drive current.
- Five thin hall wires — red (+5 V), black (ground), and yellow, green, blue for the three hall signals.
- A ninth wire, if present, is usually a temperature sensor.
Always start with colour-to-colour
Phase yellow to yellow, green to green, blue to blue. Same for the hall signal wires. On matched parts this is normally correct, and you are done.
If it is not right, read the symptom
| What the motor does | What it means | Next move |
|---|---|---|
| Spins smoothly, correct direction | Correct | Stop. Tidy the cables. |
| Spins smoothly, backwards | Very close | Swap any two phase wires. |
| Judders, stutters, cogs | Commutation out of sequence | Leave phases alone. Cycle the three hall signal wires through all six orders, testing each. |
| Will not turn, or locks up | Wrong combination | If all six hall orders fail, restore them, change the phase order, and repeat the six hall orders. |
| Runs but draws heavy current, gets hot | Wrong and damaging | Disconnect immediately. Continuing will cook the motor and controller. |
How to know you found the right one
Not just "it turns". The correct combination runs smooth and quiet, in the right direction, and draws the lowest no-load current of any combination you tried. If two combinations both turn the wheel, keep the one that draws less.
If your motor has no working hall sensors
Some controllers run sensorless, using only the three phase wires. Expect a hesitant start and weak low-speed pull, with normal behaviour once moving. It is a legitimate rescue for a motor whose halls have died when you would rather not replace the whole wheel.
Motors and motor wheels Complete wheels come with the motor already laced, which removes the wheel-building step entirely. Not sure what's wrong? Run the three-minute check first — most pedal-assist faults need no new part at all.RideRow sells replacement parts and provides installation information. We do not perform repairs. Installation is carried out by you or a technician you choose.