How Fast Do eBikes Go? The Real Numbers

Three numbers cover almost the whole world, and which one applies to you is a question of geography rather than engineering.

In the US, **Class 1 and Class 2 bikes cut assist at 20 mph** and **Class 3 cuts at 28 mph**. Across the **EU the cap is 25 km/h**, flat, with no classes involved at all. A bike built for the German market and one built for the American market can share a motor, a frame and a battery, and still stop helping at different speeds, because the only real difference is a setting.

What the cap does is worth being precise about. It does not brake you. It is not a governor fighting your legs. The motor simply stops adding power, and from that moment you are riding an ordinary bicycle that happens to weigh 22 to 30 kg. Nothing dramatic happens. The assistance just leaves, quietly, like someone remembering another appointment.

Because the rules are regional and change more often than the hardware does, check yours rather than the spec sheet: PeopleForBikes tracks the US state picture, and the UK government rules for electric bikes cover the 15.5 mph European-style limit. Our classes explainer is the long version of what Class 1, 2 and 3 actually mean.

As fast as your legs can push a heavy bicycle, which is a sentence that answers itself for most people.

On the flat, past the cut-off, you are fighting air resistance with no help at all, on a machine carrying a motor and a battery you are no longer being paid back for. Riders who are strong and determined get a bit above the cap. Everyone else discovers that the cap and their honest top speed are roughly the same number, which is a tidy piece of design if you think about it.

Downhill is the exception, and it is a large one. Gravity has not been regulated yet. A 25 kg bike with a rider on a decent descent will pass any assist limit comfortably and legally, because no motor is involved in doing it. This is also the moment to remember that you are now stopping 25 kg rather than 11, which is exactly why hydraulic disc brakes are worth the money on a heavier bike.

The other thing that happens past the cut-off is that people go looking for a way around it, which brings us to the section that will annoy somebody.

Here is the number the marketing never mentions: your average speed has almost nothing to do with your top speed. It is set by junctions.

A city ride is a sequence of accelerations and stops. Traffic lights, give-ways, pedestrians, that one roundabout everyone in your town complains about. You spend a surprising share of any urban journey doing nought, and no motor on earth improves your average while you are stationary at a red light contemplating your choices.

Do the arithmetic on your own commute rather than trusting a headline. A 12 km ride averaging 20 km/h door to door takes 36 minutes. The same 12 km averaging 24 km/h takes 30. Six minutes is a real difference and worth having, but notice that neither figure is anywhere near 25 km/h of assist, let alone 28 mph, and notice that the thing which moved it was fewer stops rather than more power.

We had a customer who paid a large premium for a 140 km range model to cover a 12 km commute. Lovely bike. They were hauling a heavier battery they charged once a week and never came close to emptying, and the right bike was two grand cheaper. We told them, they bought the cheaper one, and they thanked us for it. The same mistake gets made with speed, just with fewer people willing to admit it afterwards.

Slower than the cap, and this is where bikes that share a top speed stop resembling each other at all.

On a climb you are no longer limited by the speed setting. You are limited by torque, which is the twisting force the motor can actually produce, measured in newton metres. Two bikes can both cut out at 25 km/h and behave completely differently on a hill, because one of them runs out of pulling power at walking pace and the other does not.

So here is the opinion I will defend at length and have, repeatedly: **more watts is not more better.** Watts describe electrical draw. A well-tuned 250 W mid-drive out-climbs a crude 750 W hub motor on a real hill, because the mid-drive puts its power through the gears and multiplies it, while the hub is stuck turning the wheel directly at whatever speed the wheel happens to be turning. The headline wattage tells you what the bike consumes, not what it can do. Hub motor vs mid drive goes through the mechanism properly.

Headwinds work the same way and feel worse, because at least a hill has the decency to be visible. Expect a genuine hit to your speed on an exposed route, and expect your range to take one too, since holding speed against resistance is the most expensive thing the battery ever does.

In the US, a Class 3 at 28 mph. In the EU, 25 km/h. Those are the ceilings, and everything sold above them is a different category of vehicle wearing bicycle clothing.

The machines advertised at 45 or 50 mph are not fast e-bikes. They are electric mopeds or light motorcycles, and in most places that means registration, a licence, insurance, a plate and no legal access to bike paths or cycle lanes. They can be a perfectly good thing to own. They are just not the thing you thought you were buying, and finding that out from a police officer is the expensive way.

Which covers derestricting, briefly. Yes, the tuning kits exist. They void the warranty on every bike we sell, they can reclassify your bicycle as an unregistered motor vehicle, and they put a drivetrain and a set of brakes under loads they were never specified for. If you genuinely need to go faster than 28 mph, buy the vehicle that is designed and certified to do it, rather than persuading a bicycle to pretend.

There is also the quiet trade-off nobody mentions when selling a Class 3: holding a higher speed costs battery. Real-world range across our range runs 45 to 110 km, and the top of that band is not achieved at 28 mph into a headwind. Speed and distance are drawn from the same account.

On a flat, calm, uninterrupted road, a reasonably fit rider on a normal bicycle is not far off an e-bike, because both are close to the assist cut-off anyway. That is the case people quote when they want to argue the motor is pointless, and on that specific road they have a point.

It falls apart everywhere else. From a standstill at a light, on any gradient, into wind, or with a load on the back, the gap is not subtle. More importantly, the e-bike average holds steady across a whole week, while the unassisted average quietly drops as the rider gets tired, or takes the flat route, or drives instead because it is Thursday and the hill has won.

The measurable difference is not speed, it is that you arrive without needing a shower. That is the thing which makes riding to work survive contact with real life, and it is why people who gave up on an ordinary bicycle stick with an e-bike. Ebike vs regular bike compares them properly, including the parts where the normal bike wins.

**If your route is flat and full of junctions, buy the slower bike.** You will never hold 28 mph on it. You will pay more, carry more weight, and accept more legal restriction in exchange for a number you get to use on about four hundred metres of your commute.

**If you ride on shared paths or cycle tracks, check before you buy.** Plenty of jurisdictions allow Class 1 and Class 2 on bike paths and exclude Class 3 entirely. Buying the fast one and then being unable to legally ride it on your own route is a genuinely miserable way to spend money.

**If a helmet law or a minimum age applies to Class 3 where you live, factor it in.** These vary by state and country and are the sort of detail that only becomes interesting after purchase.

The rule of thumb I give people: buy for the speed you will actually average, not the one printed on the box. Nine times out of ten that means a Class 1 or a 25 km/h bike is plenty, and the money saved is better spent on a torque sensor, decent brakes and lights that work. If you want the fuller version of that decision, our guide to choosing an ebike walks through it. Every bike we send out is workshop-checked before dispatch rather than drop-shipped from a warehouse that has never seen it, and if you tell us your route we will happily talk you down a category when the cheaper bike is the right one.