How Fast Can Electric Bikes Go?

[Dr_Paul]

Does anyone know how fast electric bikes can go? I'm intrigued, not because I wish to buy one (I'm happy with my ordinary bike), but because I was driving down the A316 (Lower Mortlake Road) from the Gasworks Bridge at 30mph and noticed that the electric bike -- one with a big rear hub on an ordinary-looking bike -- which I was thinking I'd be overtaking was actually going the same speed as me along a level stretch of road all the way to the roundabout at Richmond. I've not seen one go this fast before.

 

[stuu]

I saw somone on one of those the other day, it was easily doing 35, dodging in and out of traffic like it was in a car chase. I didn't realise they could go that fast either, and they can't legally

 

[alxndr]

Legally, as fast as you can pedal them (although the motor won’t be assisting at that point).

Illegally, I’m not surprised at those speeds.

Its a shame as they’re very good at making cycling more accessible and practical for transport, but people who don’t behave sensibly risk ruining that for all of us.

 

[JohnMcL7]

For an e-bike to be considered the same as a normal non e-bike the motor assist is limited to 15.5mph as well as only engaging when the pedals are being used and limited to 250W power. If the bike doesn't meet all these conditions then it's legally a motor vehicle and comply with much tougher regulations including insurance, VED, number plate etc.

I've seen a couple of blatantly illegal e-bikes, one was a purpose built bike costing around £10K which could do 45mph and sold in the UK with a limited power mode for use while on the road. I'm not sure this would comply legally and there was an e-bike company who were fined for selling e-bikes that weren't legal even though the e-scooter sellers get away with saying they're not for public use. The other one I've seen sounds similar to the one the OP saw, a normal hardtail bike with a motor hub and looked to be doing easily 30mph+ given he was outpacing traffic in a 30.

The first one I used to see around on a semi-regular basis and have wondered if the police caught the rider as his riding style made it blatantly clear the bike wasn't legal. I've seen a big increase in ebikes over the last couple of years and it's rare to see one being used illegally.

 

[BananaRepublic]

One of the most frequently asked questions concerning E-bikes is about their speed.
The first thing to remember is that even though E-bikes have a motor, they are still bicycles and not scooters.

In Europe, an E-bike can have a maximum power of 250 watts, assisting the E-Bike to a maximum speed of 15.5 mph (25 km/h).

In the U.S., the rules are different.
There, E-bike motors can have a maximum of 500 watts and assist up to 20 mph (32km/h)

There are also E-bikes that support up to 45km/h (28 mph).
These are referred to as pedelecs.

An E-bike can surpass the speed of its support level, but the motor stops supporting you when you reach the max speed limitation.

 

[dcbwhaley]

For an e-bike to be considered the same as a normal non e-bike the motor assist is limited to 15.5mph as well as only engaging when the pedals are being used and limited to 250W power. If the bike doesn't meet all these conditions then it's legally a motor vehicle and comply with much tougher regulations including insurance, VED, number plate etc.

I've seen a couple of blatantly illegal e-bikes, one was a purpose built bike costing around £10K which could do 45mph and sold in the UK with a limited power mode for use while on the road. I'm not sure this would comply legally and there was an e-bike company who were fined for selling e-bikes that weren't legal even though the e-scooter sellers get away with saying they're not for public use. The other one I've seen sounds similar to the one the OP saw, a normal hardtail bike with a motor hub and looked to be doing easily 30mph+ given he was outpacing traffic in a 30.

The first one I used to see around on a semi-regular basis and have wondered if the police caught the rider as his riding style made it blatantly clear the bike wasn't legal. I've seen a big increase in ebikes over the last couple of years and it's rare to see one being used illegally.

To be pedantic the motor must have a nameplate rating of no more than 250w. But the motor on my e-bike, despite being rated at 250w, pulls 400w on the top setting.
It is possible to hack the software in the controller to give a higher top speed.
The higher powered, faster e-bikes are sold on the understanding that they will only be used off road. A stipulation which is always adhered to :-]
An e-bike doing 30mphg could, of course, be being pedalled at that speed.

 

[Ediswan]

To be pedantic the motor must have a nameplate rating of no more than 250w. But the motor on my e-bike, despite being rated at 250w, pulls 400w on the top setting.

The type of electric motors used tend to be rated as their maximum continuous power (30 minutes). Hence, no surprise that the legislation refers to maximum continuous rated power. Maximum achievable power will be higher, subject to what the electrical system can supply of course.

Does the rating have to be accurate (not deliberately derated) ? I have no idea.

 

[jon0844]

Bicycle delivery drivers certainly seem to favour the illegal bikes that also don't require pedalling (which is one way to tell). Sadly these people riding on the clock are a nightmare!

My bike is limited to 15.5mph and that's fine for my needs.

 

[computerSaysNo]

Bicycle delivery drivers certainly seem to favour the illegal bikes that also don't require pedalling (which is one way to tell). Sadly these people riding on the clock are a nightmare!

My bike is limited to 15.5mph and that's fine for my needs.

I'm aware of a type of electric "bicycle" used for cargo deliveries which has no physical connection between the pedals and the wheels. The pedals are on a chain to a freely-rotating hub with a rotation sensor, which then sends a signal to the electrical system to apply propulsion. The signal is binary i.e. as long as you're pedalling (regardless of pedal speed) the system will try to reach maximum speed (~15mph, see below). The hub is independent from the rest of the system and as such is never under any resistance beyond that of the rotation sensor.

The issue with this setup is that when you start pedalling there is a delay while the system starts up, where you are pedalling but not getting any forward propulsion. To combat this there is a separate thumb-operated throttle button which provides immediate forward propulsion, for use e.g. when pulling out at junctions.

The thumb-operated button will only propel the bike up to about 3mph while the speed using the pedals is capped at about 15mph. There is no speedometer fitted to the bike which you are able to see.
From this setup it feels to me like a low-speed electric motorbike but they've just added in the pedals to make it comply with the bicycle legislation.

The bike has "wing" mirrors although these are tiny and are mounted to the handlebars so are useless if you apply any steering at all.
The bike has directional indicator lights although these are mounted only on the rear, therefore oncoming traffic is unable to see you indicating unless you use hand signals.


So yes anyway, to answer the question "how fast can electric bikes go", the one I've mentioned above is capped at, at most, 15.5mph, and due to the pedals being mechanically separate from the wheels I would imagine it would be impossible in practice to exceed this speed.

 

[341o2]

The firm fined for illegal ebikes is Mate Bike, the bikes they sold had motors rated at 750w, and were capable of 32km/hr (presumably with motor assist). They also had to recall all the bikes.

https://ebiketips.road.cc/content/n...w-20mph-e-bikes-and-told-to-issue-recall-4005

At the risk of being pedantic, an ebike can go faster than 15.5mph, but only by pedalling. The motor should cut out at this point
Also, you cannot "just add pedals to make it look like a bicycle. (as happened in the past with certain mopeds)
The bike must be fitted with pedals that are capable of propelling it

 

[alxndr]

I'm aware of a type of electric "bicycle" used for cargo deliveries which has no physical connection between the pedals and the wheels. The pedals are on a chain to a freely-rotating hub with a rotation sensor, which then sends a signal to the electrical system to apply propulsion. The signal is binary i.e. as long as you're pedalling (regardless of pedal speed) the system will try to reach maximum speed (~15mph, see below). The hub is independent from the rest of the system and as such is never under any resistance beyond that of the rotation sensor.

The issue with this setup is that when you start pedalling there is a delay while the system starts up, where you are pedalling but not getting any forward propulsion. To combat this there is a separate thumb-operated throttle button which provides immediate forward propulsion, for use e.g. when pulling out at junctions.

Is this not just a cadence sensor? There are also many more legitimate e-bikes with cadence sensors, my partner has one (although theirs has a speedo and no throttle at all). There is very little difference between theirs and my torque sensing one, except for at slow speeds when you can feel the jerk of the motor kicking in. Torque sensors give a smoother transition between no assistance and assistance. I can ride both just as sensibly as I can the non-electric bike we have.

 

[computerSaysNo]

Also, you cannot "just add pedals to make it look like a bicycle. (as happened in the past with certain mopeds)
The bike must be fitted with pedals that are capable of propelling it

Do you have a source for this?
I've tried searching online but the only thing I can find is this government webpage which doesn't use particularly legal-sounding language.
For example:

An EAPC [electrically assisted pedal cycle] must have pedals that can be used to propel it.

But this only implies that the pedals shall propel the cycle independent of the motor. Push-type pedals that you would find in a car still come under the dictionary definition of a "pedal". If you fitted one of these to an electric bicycle instead of the "manual" pedals, chain and gears, that new pedal would then, when pressed, propel the bike, thus satisfying the quoted condition, no?

 

[stuu]

But this only implies that the pedals shall propel the cycle independent of the motor. Push-type pedals that you would find in a car still come under the dictionary definition of a "pedal". If you fitted one of these to an electric bicycle instead of the "manual" pedals, chain and gears, that new pedal would then, when pressed, propel the bike, thus satisfying the quoted condition, no?

I doubt it, the pedals in that case don't propel the bike, they cause a motor to propel the bike which isn't the same thing

 

[Magdalia]

I ride an ebike. The instruction book says the following:

• The motor may only be used to assist pedalling, it must only "help" when the bike user applies effort to the pedals him or herself. The walk assist function is an exception to this - it helps when wheeling the bike.
• The average motor power rating must not exceed 250kW. As speed increases motor power must continue to drop progressively.
• The motor must cut out at approximately 25km/h.

25km/h is also approximately 15mph.

 

[Dr_Paul]

Thanks for the replies. Is it possible for someone with the technical knowledge to tweak an electric bike so that the motor doesn't cut out at 15mph/25kmph?

 

[JohnMcL7]

Thanks for the replies. Is it possible for someone with the technical knowledge to tweak an electric bike so that the motor doesn't cut out at 15mph/25kmph?

Yes, I believe there's a number of ways to bypass the limits on an e-bike.

 

[LSWR Cavalier]

How fast "can" they go, or how fast "may" they go?

I think they should perhaps be allowed to go faster and be treated as motor vehicles, not cycles. Perhaps use of the motor should trigger a warning sound too.

 

[johncrossley]

I think they should perhaps be allowed to go faster and be treated as motor vehicles, not cycles.

That's called a moped.

 

[Busaholic]

The Delfast Hot 3.0 advertises a 50 mph top speed, but will apparently go a bit faster: it also claims a range of 200 miles and features in the Guinness Book of Records. Whether any examples have been imported from the USA I've no idea, but I do know a very handy man near to where I live in Cornwall who has a sideline in building ebikes from scratch to order, and I have witnessed a couple of them going at eyewatering speeds, including up a steep hill, when I've been out in my car. All quite illegal of course.

 

[dcbwhaley]

To combat this there is a separate thumb-operated throttle button which provides immediate forward propulsion, for use e.g. when pulling out at junctions.

The thumb-operated button will only propel the bike up to about 3mph while the speed using the pedals is capped at about 15mph. There is no speedometer fitted to the bike which you are able to see.
From this setup it feels to me like a low-speed electric motorbike but they've just added in the pedals to make it comply with the bicycle legislation.
rom the wheels I would imagine it would be impossible in practice to exceed this speed.

The thumb button is no longer permitted under current legislation but does have "grandfather rights". And some bike shave the button with the proviso that it is only for off road use.
My bike has such a button which applies maximum power to the motor. That permits you to drive it as motorbike but for only twenty minutes or so before the battery expires.
The controller on most e-bikes includes a speedometer

 

[jon0844]

My bike throttle will go to 3 or 4mph, mostly to help you get moving, but once pedalling with low assist will take it up to 100% assist as long as you keep pedalling.

This means I can cycle with low to moderate assistance and boost as required - but always pedalling.

If assist is off (but the motor is on) the throttle goes back to only giving that 3-4mph boost and won't give any power when pressed. Not sure if that's a requirement or just how this individual bike is configured.

 

[thaitransit]

Illegally there was a guy in Queensland who rode an E bike that had been modified at 110kph down a highway. He was brave to do that as one rock on the road and he would have been flying.

Normal legal E bikes max out at about 40kph.

 

[Ducatist4]

There are E bikes (15.5mph and pedals) and there are electric motorbikes (like real motorbikes but electric) and many people have trouble telling the difference between them (including the Police). The SURON electric motorbikes that you see around will do sixty miles an hour but their own web site blurs the difference between the two types of bike.

 

[Bletchleyite]

There are E bikes (15.5mph and pedals) and there are electric motorbikes (like real motorbikes but electric) and many people have trouble telling the difference between them (including the Police). The SURON electric motorbikes that you see around will do sixty miles an hour but their own web site blurs the difference between the two types of bike.

It's not made easy for them by some e-bikes being designed to look like motorcycles, e.g. with smaller wheels and thick tyres, mostly for the youth market who think riding a motorbike is cool.

(see also 50cc "mopeds" designed to look like proper motorcycles - my sister got one when she was 16).

 

[Aviator88]

Legally the (maximum) 250 watt motor can assist up to a speed of 15.5 mph.

Practically, the laws of physics apply - a 1,000 watt motor will take a bike up to ~ 35 mph, a 2,000 watt motor up to ~ 45 mph etc.

 

[jackot]

Have a look at these if you want to know what a fast one looks like. Obviously not road legal, but the line seems very blurred here between it being an e-Bike or more like an electric motorcycle.
These will do 70+ mph, with a 27KW motor! A friend of mine had a go on one in the Czech Republic and thought 20mph on it felt rapid.

 

[Ducatist4]

They are not E Bikes, they don’t have pedals.

 

[Aviator88]

Have a look at these E-Bikes if you want to know what a fast one looks like. Obviously not road legal, but the line seems very blurred here between it being an e-Bike or more like an electric motorcycle.
These will do 70+ mph, with a 27KW motor! A friend of mine had a go on one in the Czech Republic and thought 20mph on it felt rapid.

That's a thing of beauty! If only we lived in a world where everybody was responsible and accountable, they'd take 80% of the local traffic off the roads...

 

[Bletchleyite]

That's a thing of beauty! If only we lived in a world where everybody was responsible and accountable, they'd take 80% of the local traffic off the roads...

I can't see why I would want to ride an electric or petrol motorcycle. That's just an electric motorcycle. People who like riding motorcycles and have a motorcycle licence will buy them.

If you think motorcycles are a solution on their own, try going to Vietnam then I will ask you that again.

 

[Aviator88]

I can't see why I would want to ride an electric or petrol motorcycle. That's just an electric motorcycle. People who like riding motorcycles and have a motorcycle licence will buy them.

If you think motorcycles are a solution on their own, try going to Vietnam then I will ask you that again.

Hence the comment on responsibility and accountability