Electric Bike Buying Guide
What the numbers on a specification sheet mean, which ones matter for your riding, and which ones are mostly marketing.
Start with the route, not the bike
The most common buying mistake is choosing a specification first. Start instead with three facts: how far you ride in a typical round trip, what the surface and gradient are like, and where the bike will be stored. Those three answers eliminate most of the catalogue before you have looked at a single motor figure.
Motors
Hub motors sit in the wheel — usually the rear. They are simple, quiet, inexpensive to produce and put no extra load on the chain. Mid-drive motors sit at the crank and drive through the bike’s gears, which means they multiply torque on climbs and keep the weight low and central. Mid-drives generally climb better and handle better; hub motors are generally cheaper and need less drivetrain maintenance.
Nominal wattage is the continuous rating and is the number used in most legal definitions. Peak wattage is a short-burst figure and is not comparable between manufacturers. Torque in newton-metres is the most useful single number for how strong a bike feels from a stop and on a hill.
Batteries and range
Watt-hours (volts × amp-hours) is the capacity figure to compare. A 48V 15Ah battery holds 720Wh. Claimed range figures come from favorable test conditions — flat ground, light rider, low assist, mild weather. Your range will be lower if you are heavier, carry cargo, climb, ride into wind, ride in the cold, run low tire pressure, or use high assist levels.
Also check whether the battery is removable, since that decides whether you can charge indoors and store it warm in winter, and confirm the charging time and charger type on the product page.
The three-class system
| Class | Assist type | Assist cut-off |
|---|---|---|
| Class 1 | Pedal assist only, no throttle | 20 mph |
| Class 2 | Pedal assist plus throttle | 20 mph |
| Class 3 | Pedal assist, throttle limited or absent | 28 mph |
Where each class may be ridden is set by state and local law and by individual land managers. See E-Bike Laws by State.
Brakes
Electric bikes are heavier and faster than conventional bicycles, so braking matters more. Mechanical disc brakes are serviceable and inexpensive. Hydraulic disc brakes give more power for less hand effort and are more consistent when wet or on long descents. On cargo bikes, trikes and anything you will ride loaded or in winter, hydraulic brakes are worth prioritizing.
Frame fit and payload
Check the manufacturer’s rider-height range and standover height. Then check maximum payload, remembering that it includes the rider, all cargo and every fitted accessory — not cargo alone.
Certification and safety
Battery and system safety certifications such as UL 2849 and UL 2271 are increasingly required by insurers, landlords and some municipalities. We publish a model’s certification status exactly as the manufacturer documents it, and mark it as awaiting confirmation when we have not received documentation. We do not claim certifications on a supplier’s behalf.
Buying guide questions
Is more motor wattage always better?
No. Nominal wattage describes continuous output, not how the bike feels. Torque, measured in newton-metres, is a better guide to acceleration and hill climbing, and the sensor type determines how naturally the power arrives. A 500W mid-drive with a torque sensor can feel stronger on a climb than a 750W cadence-sensor hub motor.
How do I work out the battery capacity I need?
Multiply battery voltage by amp-hours to get watt-hours, which is the figure to compare across models. Then look at the manufacturer’s claimed range, treat it as a best case, and check it against your real round trip plus a margin for hills, cold and headwind.
Torque sensor or cadence sensor?
A cadence sensor detects that you are pedaling and applies a set level of power. A torque sensor measures how hard you are pedaling and scales power to match, which feels more like a stronger version of your own effort and is generally preferred for hills and technical terrain. Cadence systems are simpler and often less expensive.
What frame size do I need?
Use the manufacturer’s published rider-height range on the product page as the starting point, and check standover height against your inseam. If you are between sizes or near the edge of a range, contact us before ordering and we will check the geometry with the supplier.