Replacing or Upgrading Hub Motor Wires

October 27, 2012

This is the first in our series of ebike repair stories. Also, replacing the wires going into your motor is a great first step in hotrodding your hub motor since burned wires is the #1 reason for failure in an overvolted overwatted hub motor. (read our hotrodding hub motor story).

For an example how effective such a motor can be, one builder/racer modified his $100 9C motor by upgrading to thicker wires and was the first electric bicycle to finish Pikes Peak in 2012, finishing ahead of a team of $15,000 Optibikes. (read his inspiring story)  The motor in the pictures is the same 9C motor this builder used to win Pikes. In any case, upgrading or repairing the wires going into a hub motor is not an easy task, and this step-by-step pictorial guide should make it easier for you.

One common issue with hub motors is broken or shorted wires at the point where the wires exit the motor axle. If the wires are tugged or twisted the sharp edges of the hub motor axle can cut through the wire insulation or completely sever the wires. Most hub motors employ hall sensors to tell the controller the motor position. Hall sensors are easily burnt out if the signal wires short to power or ground. The motor shown below stopped functioning after the wires were damaged. A quick test showed that the hall sensors were burnt out. (Testing Hall sensors article to come).



To read the rest of this extensive  story go here  to our repair section.


Eric has been involved in the electric bike industry since 2002 when he started a 6000 square foot brick and mortar Electric Bike store in downtown San Francisco. He is a true believer that small electric vehicles can change the way we operate and the way we think.


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