Steve Belliveau’s 52.8 kW-Peak 2004 KX250F Electric Conversion

Steve Belliveau did not just pull the engine out of a 2004 KX250F and stuff an electric motor into the empty space. He tore this bike all the way down, replaced everything that could wear out, and rebuilt it as a purpose-built electric weapon for motocross, freestyle, trails, enduro, and the occasional blast down the street.

The result is old-school Kawasaki motocross attitude backed by a seriously modern power system—and one hell of a clean conversion.

Built around serious power

At the center of the build is the 2026 version of the QS165 60H V3. It is rated at 12 kW, but Steve built the supporting system with enough electrical headroom to let this motor eat.

Motor: 2026-version, 12 kW-rated QS165 60H V3.
Gearcase: GritShift billet anodized cover, selected for greater strength, increased oil capacity, cooler operation, and longer oil life.
Motor installation: Five custom-fabricated mounts welded to the frame, plus a 3/16-inch aluminum bracket at the left rear mounts. The bracket is tied into the swingarm bolt with 7 mm-wall aluminum spacers.
Controller: 2026 CAN-version Fardriver ND961200-HA90 with a bolt-on finned heatsink and CPU-grade thermal paste. It is mounted in a modified airbox with the full heatsink exposed forward behind the shock, supported by custom aluminum mounts on the rear subframe.
Throttle: FX throttle.

Gearing and AmpSprockets setup

Steve changes the front sprocket to suit the riding planned for the day, using AmpSprockets 520 11T, 12T, and 13T front sprockets. The rest of the final drive pairs a Supersprox 520 49T rear sprocket with a Primary Drive X-Ring 520 chain in a 114-link configuration.

The electrical system to back it up

A strong motor is only as good as the battery, controller, and wiring feeding it. Steve did not cut corners here.

Current battery: 24s10p EVE 50PL 21700 pack, 50 Ah and 88 V nominal.
BMS: ANT 420 A continuous / 1,050 A peak, currently limited to 600 A peak.
Power potential: At 88 V nominal, the 420 A continuous BMS rating represents approximately 37 kW of theoretical battery-side power. The configured 600 A peak limit raises that short-duration potential to approximately 52.8 kW, subject to voltage sag and the limits of the controller, motor, and complete electrical system.
Current delivery: WellGo 1 mm custom copper bus bars, dual QS10 connectors, and dual 4 AWG cables. A triple-QS8 configuration is under consideration.
Planned battery: 26s10p Tenpower 60XG 21700 pack, 60 Ah and 96 V nominal.
Display: Chaojie 3.13-inch TFT CAN display.
Lighting and wiring: LED headlight and taillight with functional brake light, plus completed custom full-chassis and controller harnesses. Steve built the harnesses from a mix of materials already in the shop, so the wiring and heat-shrink colors vary, but every component is properly sized and rated for safe, precise operation. Once the bike is assembled, the harnesses are nearly invisible unless you know exactly where to look.
Controls: BEP Marine kill switch mounted where the fuel cap was, matching keyed ignition, and a momentary pre-charge button using a 40 W, 250-ohm ceramic resistor pack.

Finding the real power limit

Steve plans to put the bike on a dyno and keep increasing current until the motor reaches the point where more amperage stops producing meaningful power and only creates additional heat. That testing should provide real performance numbers early next year.

The rest of the bike got the same treatment

Power was only half the job. The chassis, suspension, controls, and finishing details were rebuilt to match the level of the electric conversion.

The motorcycle was completely rebuilt from top to bottom, including replacement of every use-related wear component.
Fork and shock re-valved by Factory Connection.
2014 front rim laced to the original 2004 hub, paired with 2014 fork guards and custom graphics.
N-Style fender and shroud graphics, a custom Energy seat cover, and Guts Racing medium seat foam.
Left-hand brake conversion with a brake switch.

This is the kind of conversion we love to see: thoughtfully engineered, properly fabricated, ridiculously capable, and built to be ridden—not parked.