How would you build a 1kW SEL?

[Arbol]

Inspired on the thread:

http://www.pedelecs.co.uk/forum/threads/road-legal-1000w-electric-scooter.17048/

and despite the fact I am not talking about pedelecs, but a SEL (I do not know how to translate it into English, I would say this is a light electric motorcycle, which can be used without license / insurance / ...), I would like to ask opinions on this subject.

As I said in that thread, in Barcelona SELs with less than 1kW, a max speed of 25km/h and I believe a regulation in weight (50kg max), can be driven without license / insurance / ... They need to be driven through lanes specific for bikes. But this is not a huge restriction, since basically you can move to any place within the city with lane specific bikes.

There is a company offering these vehicles, which are used basically by tourists (rent). In fact, this is the only usage I have seen so far, locals do not use them.

http://www.urbanfun.es/scooter/e-zip-1000-pro.html

As you can see, the specs are a bit outmoded: a DD motor and SLA batteries (gasp!).

From what I see here, a 1kW / 25km/h max speed could easily be accomplished with standard motors, such as a BPM. The only odd issue is wheel size, those scooters use small rims, so I do not know how and if a BPM style motor could fit.

With 18650 batteries such as the Panasonic 18650PD, one could make wonders in terms of performance and weight.

How would you build from scratch such a vehicle? The idea would be a shape similar to the Currie model above, but possibly with slightly larger wheels to put a BPM style motor, better batteries, in general better (lighter) components, and having the same spirit as in the Currie, with the foldable handlebar, such that easily one may have a small and light "package" that can be put in a lift, charged easily at home and "parked" at say the balcony.

This product is apparently only useful in Barcelona, but I would not be surprised if in the future, European regulations allow a widespread usage of this kind of vehicles.

Any ideas are welcome.

 

[Arbol]

For example, something as extremely small as:

http://www.alibaba.com/product-detail/electric-scooter-motors-sale_1281759606.html

But made with good quality components.

Or maybe a 16'' configuration, like a Brompton, in order to have standard foldable bike components, and a decent quality ride (maybe small rims are too uncomfortable, I have never tried them).

 

[flecc]

This product is apparently only useful in Barcelona, but I would not be surprised if in the future, European regulations allow a widespread usage of this kind of vehicles.

Unlikely, the latest EU regulations and proposals include this non-pedalling class as mopeds, and those1000 watt ones with pedals come under the low-powered moped class. Both are considered motor vehicles and subject to having the right driving licence, the P1 class in our case.

Even the S class higher speed e-bikes with up to 500 watts have to have a form of registration with number plates and insurance.

 

[Arbol]

Interesting, thanks. Is there a link where the different EU regulations and proposals are described? I only knew the traditional "pedelec 250w", I did not know there was a 500w class (or different moped ones).

 

[flecc]

Interesting, thanks. Is there a link where the different EU regulations and proposals are described? I only knew the traditional "pedelec 250w", I did not know there was a 500w class (or different moped ones).

Overall the legislation is very complex, but here are a number of links for you:

Two links to UK e-bike law. N.B. The 200 watt limit has a 250 watts waiver now.

The Electrically Assisted Pedal Cycles Regulations 1983

The UK Construction and Use regulations for all bicycles

EU wide Type Approval including the UK

Vehicle categories : N.B. Scroll down to article 4

Overall list of directives and legislation

The Single Vehicle Approval Guide describes the two wheel motor vehicle groups available to us in the UK. Scroll three-quarters way down for the types, basically low-powered moped, moped and motorcycle. E-bikes are not classed as motor vehicles of course.

This isn't everything since not all is readily available. There's also the EN15194 EU electrical standards regulation.
.

 

[Arbol]

Thanks. And in the UK, what are the requirements to drive a "Low powered moped"? Is it necessary to register / pay taxes / get insurance / ... as in a car? or the process is somewhat more streamlined?

 

[flecc]

Thanks. And in the UK, what are the requirements to drive a "Low powered moped"? Is it necessary to register / pay taxes / get insurance / ... as in a car? or the process is somewhat more streamlined?

Yes, but exactly the same as the usual 30 mph moped, a P1 licence is needed, unless a car driving test was passed before 1st February 2001.

Insurance is the same as moped but VED (formerly Road tax) is free for electric mopeds.

 

[Arbol]

Mmm reading the "maximum 250w continuous" makes me ask:

Usually we think of power as voltage times amperage. For example, if the battery gives 36V and the controller is of a max of 15A, max power is then 540W.

But most 18650 cells are quoted as 0.2C by the producer. So, if one has say 10Ah of these cells, the "max continuous" amperage should be 2A.

Assuming again 36V, this gives a "max continuous" power of 72W.

I guess that my calculation is not the legal one. But how does in practice work? I see motors of "350W" being sold legally, and run at 36V and 15A, ie 540W. I assume there are some losses from motor to wheel, but losses from 540W to 250W?

Is there a practical rule of what can be done? Example: can I have a KU123 with a 36V battery, if the battery is only able to provide 15A max, despite the controller being able to theoretically to provide more current to the motor (if the battery were stronger)?

 

[Deleted member 4366]

The specification in EN15194 is that the motor should have a maximum nominal continuous rating of 250w. There's no limit to how much power it can consume or produce. Look up the meaning of "Nominal"!

Nominal
1. (of a role or status) existing in name only.
2. (of a price or charge) very small; far below the real value or cost.
3. (Of a quantity or dimension) stated or expressed but not necessarily corresponding exactly to the real value

 

[Alan Quay]

So you use definitions 1 and 3? I've been using number 2

 

[Arbol]

The specification in EN15194 is that the motor should have a maximum nominal continuous rating of 250w. There's no limit to how much power it can consume or produce. Look up the meaning of "Nominal"!

Nominal
1. (of a role or status) existing in name only.
2. (of a price or charge) very small; far below the real value or cost.
3. (Of a quantity or dimension) stated or expressed but not necessarily corresponding exactly to the real value

Mmm interesting. So, which are the motors with a "nominal continuous" power of 250W?

There is a Bafang CST of 250W (as well as a 350W and a 500W). There is the BBS-01 of 250W (as well as a 350W, a 500W one and a 750W). The Xofo XF-V(K) is rated 350W-500W, so this one does not work legally. And the Q100 say in their description at BMSbattery they are 350W, but then at the Datasheet, it is stated they are 250W-350W.

Then, if I understand correctly, one could take a strong 250W motor, such as the Bafang CST of 250W, and put a strong controller, such as a KU123 and a big battery, and everything would be legal, right?

Is there another combination which would be even more powerful, but still remaining legal?

It is strange the regulations focus on the motor itself, and not on the power at the wheel, which is what really matters, in the end.

 

[Deleted member 4366]

The easy to get powerful motors that are labellel as 250w are the Ezee mk2, the 250w"Bafang CST and the 250W Bafafang BPM. The 250w Bafang CST gives good power up to about 22 amps. if you use a KU123 controller at 30 amps, it doesn't give noticeably more power, so no point going that high. I don't know if this is the same for the BPM and Ezee motor.

There's probably other motors too, like the Dapu, but I've only see them on OEM - now on the BH Emotion Neos and some other bikes, but not all run with high enough current to exploit the motor's full potential.

 

[Arbol]

The easy to get powerful motors that are labellel as 250w are the Ezee mk2, the 250w"Bafang CST and the 250W Bafafang BPM. The 250w Bafang CST gives good power up to about 22 amps. if you use a KU123 controller at 30 amps, it doesn't give noticeably more power, so no point going that high. I don't know if this is the same for the BPM and Ezee motor.

About the 250W Bafang CST:

1. The motor is quoted for 36V / 10s. Is it possible to run it also at 48V / 13s? Or 11s/12s?
2. The S09P is rated at 22A for both 36V / 48V, so it seems ideal according to what you say, especially if the answer to question (1) is yes. For the Q100 you found problems running sensorless. Do you think it is OK to run the 250W Bafang CST sensorless with a S09P?

Note: just as a reference, there are also other 9 FET controllers:

- Greenbikekit: 48V @ 25A http://www.greenbikekit.com/motor-controller/48v-350w-electric-bike-hub-motor-controller.html
- elifebike: 36V / 48V @ 19A http://www.elifebike.com/peng/iview.asp?KeyID=dtpic-2012-8W-QNK2.073KQ

 

[trex]

the situation gets more interesting when your bike is going uphill. Hub motors

Inspired on the thread:

http://www.pedelecs.co.uk/forum/threads/road-legal-1000w-electric-scooter.17048/

and despite the fact I am not talking about pedelecs, but a SEL (I do not know how to translate it into English, I would say this is a light electric motorcycle, which can be used without license / insurance / ...), I would like to ask opinions on this subject.

As I said in that thread, in Barcelona SELs with less than 1kW, a max speed of 25km/h and I believe a regulation in weight (50kg max), can be driven without license / insurance / ... They need to be driven through lanes specific for bikes. But this is not a huge restriction, since basically you can move to any place within the city with lane specific bikes.

There is a company offering these vehicles, which are used basically by tourists (rent). In fact, this is the only usage I have seen so far, locals do not use them.

http://www.urbanfun.es/scooter/e-zip-1000-pro.html

As you can see, the specs are a bit outmoded: a DD motor and SLA batteries (gasp!).

From what I see here, a 1kW / 25km/h max speed could easily be accomplished with standard motors, such as a BPM. The only odd issue is wheel size, those scooters use small rims, so I do not know how and if a BPM style motor could fit.

With 18650 batteries such as the Panasonic 18650PD, one could make wonders in terms of performance and weight.

How would you build from scratch such a vehicle? The idea would be a shape similar to the Currie model above, but possibly with slightly larger wheels to put a BPM style motor, better batteries, in general better (lighter) components, and having the same spirit as in the Currie, with the foldable handlebar, such that easily one may have a small and light "package" that can be put in a lift, charged easily at home and "parked" at say the balcony.

This product is apparently only useful in Barcelona, but I would not be surprised if in the future, European regulations allow a widespread usage of this kind of vehicles.

Any ideas are welcome.

I watched the two videos on the .es website, I may have missed something but these scooters seem to go up to about 12-15kph - about the slowest of all e-bikes out there, nowhere near the speed of 1000W e-bike. Perhaps they are not classified as e-bikes, which are defined as per EN15194.
Regarding the overvolting, there are plenty of choice if you buy directly from China, just look for products designed for the american market. I am usually against the use of the equipment outside the manufacturers' recommendations, that would lead to shortening the life of the motor and likelyhood of catastrophic failure.
Thinking about it, perhaps it's time for direct drive motors to make a come back because the new 2014 batteries are 20% lighter and cheaper compared to last year. Direct motors burn a bit more electricity but will outlast any hub drive or crank drive.

 

[Deleted member 4366]

About the 250W Bafang CST:

1. The motor is quoted for 36V / 10s. Is it possible to run it also at 48V / 13s? Or 11s/12s?
2. The S09P is rated at 22A for both 36V / 48V, so it seems ideal according to what you say, especially if the answer to question (1) is yes. For the Q100 you found problems running sensorless. Do you think it is OK to run the 250W Bafang CST sensorless with a S09P?
l

You can run a motor at whatever voltage you want with an appropriate controller. The power and speed go up in direct proportion to the voltage.

The 250W Bafang CST is about 250rpm, so with a 48v battery, it'll go up to 340 rpm (25 mph), which means that efficiency below 12 mph is compromised.

 

[Arbol]

You can run a motor at whatever voltage you want with an appropriate controller. The power and speed go up in direct proportion to the voltage.

The 250W Bafang CST is about 250rpm, so with a 48v battery, it'll go up to 340 rpm (25 mph), which means that efficiency below 12 mph is compromised.

I had not thought about that. Then it would be better to run the 250W Bafang CST at 36V? I do not care much about max speed, I care more about acceleration up to say 25km/h.

 

[Arbol]

the situation gets more interesting when your bike is going uphill. Hub motors


I watched the two videos on the .es website, I may have missed something but these scooters seem to go up to about 12-15kph - about the slowest of all e-bikes out there, nowhere near the speed of 1000W e-bike. Perhaps they are not classified as e-bikes, which are defined as per EN15194.
Regarding the overvolting, there are plenty of choice if you buy directly from China, just look for products designed for the american market. I am usually against the use of the equipment outside the manufacturers' recommendations, that would lead to shortening the life of the motor and likelyhood of catastrophic failure.
Thinking about it, perhaps it's time for direct drive motors to make a come back because the new 2014 batteries are 20% lighter and cheaper compared to last year. Direct motors burn a bit more electricity but will outlast any hub drive or crank drive.

No, they are not classified as e-bikes, they are classified as SELs, which is some kind of "up to 1kW, up to 25km/h mopeds".

I opened this thread because I believe with the technology discussed in this forum, one could do a SEL which would be much better quality than these SELs of the Spanish ad.

Regarding DD motors: have you seen the DD motor with cassette at xofo?

 

[trex]

no, I haven't - they may do it, the market is moving towards CST. I only saw the Heinzmann DD with CST:
http://www.ebike.heinzmann.com/en/systems/directpower/motor

 

[flecc]

No, they are not classified as e-bikes, they are classified as SELs, which is some kind of "up to 1kW, up to 25km/h mopeds".

That's the licencing class known as "Low Powered Moped" in the UK. Maximum 1000 watts, maximum motor driven speed 16 mph/25 kph.

 

[Arbol]

That's the licencing class known as "Low Powered Moped" in the UK. Maximum 1000 watts, maximum motor driven speed 16 mph/25 kph.

Yes, it makes sense. I have just seen that with the rent of these Curries, there is a basic insurance included. So I guess that in order to use one of these SEL / "Low Powered Moped", one needs to register with the municipality (which I guess is done when the purchase takes place) and one needs a basic insurance (unlike e-bikes).