You bought an e-bike online. Here is what to check before you ride it.

Box bikes arrive about 80 percent assembled, and the missing 20 percent is the part that stops you. Five checks worth doing today, from the shop that fixes them afterwards.

No lecture about where you bought it — that ship has sailed and it is genuinely fine. But a bike that arrives in a box needs checking before it carries you at 20 mph, and most people are never told what to look at.

Five things, in the order that they matter.

1. Brake rotor alignment

Spin each wheel and watch the rotor pass through the caliper. If it rubs, or the rotor visibly wobbles side to side, it was bent in transit — extremely common, and most people assume the noise is normal. It is not.

A gently bent rotor can be trued. A badly bent one needs replacing. Either way, do not ignore it: a rubbing brake heats up, wears unevenly and reduces stopping power.

2. Spoke tension

Squeeze pairs of adjacent spokes on each wheel. They should feel firm and consistent all the way around. Any that feel soft or rattle mean the wheel was never properly tensioned at the factory.

This one matters more on an e-bike than most people realize, because the wheel is carrying more weight at higher speed than a bicycle wheel was historically designed for. A loose wheel goes out of true fast and can fail suddenly.

3. Torque on the safety-critical bolts

Stem bolts, handlebar clamp, seatpost clamp, and rotor bolts. These are the ones where failure means injury rather than inconvenience, and they are routinely tightened by whoever packed the box, by feel, with no torque wrench.

If you own a torque wrench, use it — the correct figures are printed next to most of these bolts. If you do not, this is the single best reason to have the bike checked by somebody who does.

4. Headset play

Hold the front brake, then rock the bike forward and back. If you feel a knock through the fork, the headset is loose. Riding with a loose headset destroys the bearing races, and that is a considerably more expensive fix than the two-minute adjustment that prevents it.

5. Everything electrical, before you rely on it

Charge the battery fully and confirm it seats and locks properly. Cycle through the assist levels in a car park, not in traffic. Check the brake cut-off actually cuts the motor when you pull each lever — this is a safety feature and it is occasionally not connected out of the box.

If any of that sounded like a foreign language

That is completely reasonable and it is what shops are for. We assemble and safety-check bikes bought online at a flat rate, quoted before we start, and there is no judgement attached — a sizeable share of our service work is exactly this.

More detail here: Bought your bike online?