Fix a flat on a rear hub motor wheel, step by step

Rad says to turn the bike off, remove the battery and press the power button to drain leftover power (Rad Power Bikes). Himiway says never to work on the rear wheel with the bike powered on (Himiway).

On a geared bike, shift so the chain sits on the smallest rear cog. Rad rests the grips on wooden blocks so the display isn't crushed (Rad Power Bikes).

Photograph both sides of the axle before you loosen anything: washers, torque washers or arms, spacers, nuts and the motor cable route (Himiway). Rad says the order of this hardware matters for safety (Rad Power Bikes).

Find the motor connector near the chainstay. Cut only the zip ties, never the motor cable (Ride1Up). Hold the connector bodies, not the wires, and pull straight apart without twisting (Himiway, Rad Power Bikes).

Remove the torque arm bolt, or slide off the torque plates on models that have them, keeping washers with their bolt (Rad Power Bikes, Ride1Up). Then loosen the axle nuts. Many Rad and Ride1Up models use an 18 mm nut. Rad says not to take the nuts and washers fully off, while Ride1Up removes them to clear the derailleur, so follow your own model's guide.

Pull the derailleur back, ease the chain off the cog and lower the wheel out, keeping the rotor clear (Rad Power Bikes). Don't squeeze a hydraulic brake lever while the wheel is out (Aventon). Ride1Up warns not to lay the wheel on the side where the motor cable exits (Ride1Up).

Let the air out, push both beads to the middle of the rim and lever one bead off in small sections. Pull the tube out starting opposite the valve (Park Tool).

Pump the tube up and find the hole. Two slits side by side mean a pinch from low pressure. Feel carefully inside the tire for glass, wire or thorns, and check the rim strip covers every spoke hole (Park Tool). Rad says the tire is likely fine if no threads or casing show (Rad Power Bikes).

A small clean hole can be patched. Replace the tube for big tears, valve damage or several holes, and match the size on the tire sidewall (Himiway).

Put a little air in the tube, fit the valve straight through the rim and seat the beads by hand, finishing at the valve. Check that no tube is caught under the bead (Park Tool, Schwalbe). Inflate within the range on the sidewall. See set tire pressure.

Guide the rotor between the pads and seat the axle fully in both dropouts, with the hardware in its original order (Himiway). Ride1Up faces the axle cutout forward to ease strain on the cable (Ride1Up).

Refit the torque arm or torque plates first. Then snug both axle nuts evenly, a few turns at a time (Aventon), and finish with a torque wrench at your maker's spec. Specs differ by model: Rad lists 2 to 3 Nm for the RadRover torque arm bolt and 40 Nm for its axle nuts (Rad Power Bikes), while Ride1Up lists 30 Nm for its axle nuts (Ride1Up). Himiway says not to guess (Himiway).

Line up the arrows or notches and press the connector straight together without bending pins. Secure it with a new zip tie (Rad Power Bikes, Ride1Up). If pins look bent or dirty, see inspect and clean connectors.

Refit the battery. Check that the wheel is centered and spins freely, the brakes work, and the motor runs at low power in a safe spot (Himiway). If a hydraulic lever feels soft, Ride1Up suggests pumping it, and bleeding if that doesn't help (Ride1Up). See bleed hydraulic disc brakes.