[tobykeller]

how fast do electric bikes go?

Topic

[Rendel Harris]

Cugel wrote:

Many who know little of cycling seem to believe that ebikes are speed-restricted, or even forced to, 25kph. They aren’t so restricted; only the use of the motor above 25kph is disallowed. 

Quite a few whom one would imagine ought to know a little about cycling as well, several times along the Chelsea Embankment I’ve had sporty-type riders shout “illegal!” as I’ve passed them on my road ebike at 35-40kph and they’ve clocked the rear motor, even though it had cut out at 25kph hundreds of metres previously. I think not only do a lot of people not understand that there’s no speed limit on the bike itself, only on the speed it can do with the motor on, they also don’t understand that with a road ebike once you’ve got it up around 35–40kph (the motor is a great help with the first part of this, obviously) it takes very little more effort to sustain that speed than it does on a standard bike. Some experiments I have done with my power meter have shown I only need about 25W more at 40kph on the flat on the ebike than I do on my road bike, and even that is only due to the weight of the battery and motor and the fact that I use bigger and more robust tyres on the ebike (35/32 compared to 28/25 on the road bike).

[Cugel]

tobykeller wrote:

The speed of an electric bike varies depending on the type and model of the bike. In most countries, electric bikes are classified as either pedal-assist or throttle-assist, and their maximum speed is often limited by law. In the United States, for example, Class 1 and Class 2 electric bikes have a maximum speed of 20 miles per hour (32 kilometers per hour), while Class 3 electric bikes can reach up to 28 miles per hour (45 kilometers per hour) but are limited to pedal-assist only.

However, some electric bikes designed for off-road use or racing can exceed these speed limits and reach higher speeds, up to 45 miles per hour (72 kilometers per hour) or more. It’s important to note that riding an electric bike at high speeds can be dangerous and requires appropriate safety gear, training, and caution.

Yes but no but yes but ……

The speed that ebikes can go is not limited to this or that maximum by law.  Virtually every ebike can be pedalled by the rider to whatever speed the efficiency of rider to produce, and bike to use, power allows. The law only restricts the top speed above which motor power can’t be added to rider power.

Many who know little of cycling seem to believe that ebikes are speed-restricted, or even forced to, 25kph. They aren’t so restricted; only the use of the motor above 25kph is disallowed. 

This misunderstanding seems to give rise to all sorts of assumptions, for instance that:

* ebikes have to be illegally destricted if they’re to go faster than 25kph/ (In fact, the rider just has to get fitter).

* ebikes are dangerous because novice cyclists will all go at 25kph in all circumstances as the motor forces them to, so they should be banned from so-called shared paths. (In fact, ebike riders will ride in exactly the same fashion as they would on a non-ebike, well or badly as their inclinations, attitudes and abilities drive them).

[tobykeller]

The speed of an electric bike

The speed of an electric bike varies depending on the type and model of the bike. In most countries, electric bikes are classified as either pedal-assist or throttle-assist, and their maximum speed is often limited by law. In the United States, for example, Class 1 and Class 2 electric bikes have a maximum speed of 20 miles per hour (32 kilometers per hour), while Class 3 electric bikes can reach up to 28 miles per hour (45 kilometers per hour) but are limited to pedal-assist only.

However, some electric bikes designed for off-road use or racing can exceed these speed limits and reach higher speeds, up to 45 miles per hour (72 kilometers per hour) or more. It’s important to note that riding an electric bike at high speeds can be dangerous and requires appropriate safety gear, training, and caution.

[Cugel]

Steve K wrote:

Depends how fast you pedal.  But, legally, the motor has to cut out when  you get above 15.5mph.

As with all bikes, it depends on several other factors. Nor is one factor how fast you pedal but how much power you pedal at, with the motor perhaps adding various amounts until the road speed gets above 25kph. (How fast you pedal is determined by the gear ratio and the road speed).

When out and about, I notice quite a few Panzertank ebikes (those 28 kilo monsters) going everywhere at 25kph – but rarely faster. One suspects the pedaller is doing 50 watts and the Panzer is doing 250 (until the cut-off speed is reached).

Myself I have a racey Fazua-equipped ebike (Lapierre eXelius 700) that goes like a rocket, often well above 25kph, usually with the motor switched off (or even absent the frame) and me pedalling just shy of blowing up. 

Mind, I also go up long steep hills at speeds approaching 25kph, which requires another 150 watts (the maximum I allow myself) from the motor. I am once more aged 29 (not 74, at least) and at my peak!

In short, ebikes go as fast as non-ebikes, which speed varies with the available rider-power + e-power actually applied, the gradient, the tyre rolling resistance, the air-drag, the mental state of the pedaller, the rider+bike weight, the  …… . (Quite a long list of factors, really).

[HoarseMann]

You can get away with

You can get away with electric assist up to 16 mph in the UK:

https://www.gov.uk/government/publications/motorcycle-single-vehicle-approval-inspection-manual

[Rendel Harris]

Hirsute wrote:

Hirsute wrote:

If you have a bike made before (?) then it does give non pedalling assistance of a few mph.

Actually it’s still legal to have a “walking pace” throttle as long as it propels the bicycle at no more than 6 km/h; with any bike built before 2015 a throttle that can go up to the limit of 25 km/h is permitted.

[Hirsute]

Downhill with a following
Downhill with a following wind up to 40 mph.

On the flat, you can vary the assistance but as Steve says a legal bike will cut out at 15.5 mph.

Assistance is handy for heavy loads, trailers, physical impediment – knee, hip, heart, etc, age.

If you have a bike made before (?) then it does give non pedalling assistance of a few mph.

[Steve K]

Depends how fast you pedal. 

Depends how fast you pedal.  But, legally, the motor has to cut out when  you get above 15.5mph.

[Author]

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