DIY Lifan Dirt Bike to Electric Conversion - Part 1

Golden Motor Custom Pit Bike Electric Conversion – 72V 5kW Build with Vector 200

This project covers the conversion of a 149cc Lifan pit bike into a high-performance electric build using a 72V 5kW motor paired with the Golden Motor Vector 200 controller. The power source for this setup is a custom 72V 33Ah Surron battery capable of discharging at 200 amps. The build is executed in collaboration with Pete, a seasoned fabricator from GTA known for his custom EV conversions. The final result is a powerful and clean electric pit bike that’s designed to push limits.

We began by completely stripping down the pit bike, removing the engine, exhaust, foot pegs, and all excess components. Initially, the plan was to install a 3kW motor, but we later upgraded to a 5kW system for higher performance and future scalability. Before mounting anything to the frame, we ran a bench test of the motor and controller to ensure proper electrical function. We connected the phase wires—yellow to U, green to V, and blue to W—along with the hall sensor and battery leads. The throttle used was a twist throttle, which required manual wiring to match the red, white, and black wires to the controller. To simulate ignition, we used a simple paperclip in the e-lock plug just to complete the circuit. Once powered on, the motor spun up beautifully, confirming everything was working before installation.

Next, we collaborated with Pete to rework the frame and fit the larger components. The existing gussets and brackets were cut off using an angle grinder to create space for the battery and motor. We slightly bent the subframe to adjust the angle and added clearance at the base of the frame to prevent any future bottom-outs. To support the motor and battery, Pete began planning a custom mounting tray using angle iron. This bracket would secure to the original brake mount and extend under the battery, offering both strength and balance. With some light mock-ups and steel marking, we confirmed the geometry was workable and moved forward with fabricating the mounting hardware.

For the wiring phase, we used the pre-labeled wiring harness that came with the Vector 200 controller. The throttle wiring was custom-plugged, and the battery power leads were attached to the controller with the correct polarity. A key note here is the inclusion of the e-lock connection in the positive terminal of the battery to enable power. Once everything was hooked up, we turned on the battery and tested the throttle. The motor response was smooth and strong, confirming readiness for frame mounting.

We performed a final dry-fit with both the motor and battery inside the frame to verify clearances and alignment. The Surron 72V battery sat snug within the modified cradle. Clearance from the ground was confirmed to be safe, with the motor resting at an appropriate height for off-road use. Everything was aligned and ready for welding. The final bracket will be fabricated by Pete in his workshop, painted black, and bolted in to secure the motor permanently.

This wraps up the first phase of our electric pit bike build. In the next phase, we’ll head to Pete’s shop for steel fabrication and finalize the mounting. Following that, we’ll complete the full wiring with contactor and fuses, install a Cycle Analyst for monitoring, and take the bike for its first field run. If you’re interested in similar builds or custom batteries, we also offer 60V 46Ah Surron-compatible packs. Keep an eye out for part two of this project where we complete the transformation and showcase performance results.