How to choose an e-bike
Five specs decide how a bike actually feels. The rest is detail. Here is what each one does, and the number that matters.
1. Torque sensor or cadence sensor
This is the single biggest difference in ride feel, and it is the spec most listings bury. A cadence sensor only knows whether the pedals are turning, so the motor surges to a set power level and holds it — it feels like a scooter you happen to be pedalling. A torque sensor measures how hard you push and multiplies it, so the bike feels like a strong version of a normal bicycle.
Neither is wrong. Cadence suits riders who want to be carried. Torque suits riders who want to ride. But a cheap bike with a torque sensor often feels better than an expensive one without.
2. Torque, not watts
Watts get advertised; newton-metres get you up the hill. Nominal wattage is a loosely regulated number and peak wattage is nearly a marketing figure. Torque (Nm) is the one that predicts hill climbing and loaded starts. Roughly: 40–60 Nm is fine on flat ground, 60–80 Nm handles most hills, and 80+ Nm is what you want for cargo, steep terrain, or a heavy rider.
3. Watt-hours, not "range"
Claimed range is the least trustworthy number in the industry — it is usually measured by a light rider on the lowest assist on flat ground with no wind. Watt-hours (Wh) is the honest capacity spec. Wh = volts × amp-hours, so a 48V 15Ah pack is 720Wh.
A usable rule of thumb: most riders get 15–25 Wh per mile depending on assist level, terrain, and weight. A 720Wh battery is therefore a realistic 30–48 miles, not the 60+ on the box. We list both the claim and the raw Wh so you can do that maths yourself.
4. Mid-drive or hub
A rear hub motor pushes the wheel directly. It is cheaper, simpler, quieter to maintain, and works fine on flat and rolling ground. A mid-drive puts power through the chain and gears, so it multiplies torque in low gear — much better on sustained climbs and under load, and it centres the weight. It costs more and wears chains faster.
Mid-drive is worth it for steep hills, cargo hauling and trail riding. For a flat commute, a good hub motor is the better value.
5. Weight and payload
Two numbers, both routinely ignored. Weight decides whether you can get the bike up a step, onto a rack, or home after a flat battery — anything over about 70 lb is a two-person lift. Max total load (rider plus cargo plus bike accessories) is a real engineering limit, and on some bikes it is lower than buyers expect.
Watch for weights quoted without the battery. Several brands do this; a battery is 7–10 lb. We normalise to total weight and note it where the manufacturer split the figure.
A word on classes
- Class 1 — pedal assist only, cuts out at 20 mph. Allowed on most bike paths and many trails.
- Class 2 — adds a throttle, still capped at 20 mph. The most common US configuration.
- Class 3 — pedal assist to 28 mph. Fastest for commuting, but restricted from some paths and trails.
Many bikes ship in a lower class and unlock to a higher one in the settings menu. We list both the shipped class and what it unlocks to, because the shipped setting is what determines where it is legal out of the box. Local rules vary — check yours.
What we would actually check first
Open the comparison table, sort by torque, then filter to torque-sensing bikes in your budget. That single move eliminates most of the bikes that disappoint people, and it takes about ten seconds.