Conversion kits and the law

WheezyRider

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I've done a couple of conversions using DIY kits and I hope I am ok and following the rules, but the law seems a total mess and is completely confusing.

One is a LCD based Bafang 250W 36V hub drive. All labelled kit etc and should be legit, but...

According to the rules, the ability to change the cut off speed is not allowed by law, eg adding a dongle or having a switch or whatever. The trouble is, all of the LCD systems I've seen can be adjusted to increase the cut off speed. This is because they are mass produced for different jurisdictions, so need to be adaptable. Also, LCD controllers may be fitted to any wheel size, so they need to be adjustable to the wheel you have. This means it's possible to set it up with the wrong wheel size and go faster than the legal limit.

Surely this makes almost all LCD kits on the market technically illegal? (And for that matter, also probably a lot of factory made e-bikes.) Even then, if there isn't an LCD screen on the kit, there can be a significant difference in speed depending on the tyre size used. From a 20-622 to a 60-622 tyre, the circumference difference is more than 10%. This could take you from a max of 15.5 to more than 17 mph (I don't know what the leeway for error is with the 15.5 mph limit).

My other bike is a very old e-bike, which I have updated with a 250W 36V hub motor Voilamart kit (yes, I see you rolling your eyes lol - but it was cheap and I didn't want to spend a lot on this one). It came with a twist and go, so I was wondering if I am still ok legally, if I have updated the bike from a dubious brushed motor and controller, to a modern brushless motor and controller? I know that on this site they talk about bikes made before 2016 being ok to have twist and go, so the bike was legally ok originally, but if it is modified after 2016, is it still ok? I really hate PAS, it is so unnatural and quite frankly dangerous! The last thing I want is my bike to go firing off at full power, just because I've rotated the cranks to change down gear. On my commuting bike I have fitted a "dead man's handle" to the brake sensor, so the motor will not operate unless I am holding the switch down.

There is nothing on this UK gov site about pre 2016 bikes being ok with a twist and go, they just say they are illegal:


Basically, is this gov site wrong and if it is, when is a pre 2016 e-bike not a pre 2016 e-bike?

I've read the rules for the the original 1983 act and also the update in 2015, but what act applies now? I've read we are kind of harmonised with the EU, but we still have our own rules too, like the rider must be over 14. But if EN15194 applies, where does that leave DIY builders, who won't be able to get all their kit CE marked or radio interference tested? Are we only allowed to use e-bikes that have been factory manufactured and signed off as meeting the rules?

Also, is it legal to put a 48V battery on a 250W nominal 36V motor? The law seems to say that the battery voltage needs to be stated, but not that it has to correspond to what is written on the motor! And we all know that a nominal 250W motor is a load of marketing BS. They run at 15Amps x 36 (or up to 42V) during acceleration, so more than double 250W and they can run at this all day long. Are home made battery packs legal? How can they comply with EN15194?

The Voilamart controller comes with wires to override the speed limiting. Do I have to open up the controller and cut them off to make the unit legal? Could I put the controller inside a box and say have a key switch on the outside in order to do the override, would that be legal?

What happens now if someone wants to build their own e-bike from scratch? Eg a recumbent trike or whatever. Is that still allowed?

I know most people using e-bikes have got fed up with the inability of the law to keep up with technology, the market place and the real world and they are just doing what they feel is right, whatever the law says, but an old fart like me does worry about getting caught and getting the book thrown at me (riding an illegal bike without registration, tax, insurance , MOT, helmet etc etc). I know it is extremely unlikely that I would ever get stopped and have my bike checked out for legality, but my worry is if some numpty pedestrian steps out in front of me without taking their eyes off their damn phone and I hit them and injure them and the police start getting interested...

Sorry this is so long and full of questions, but I've had a lot on my mind and this is my first proper post :)

Wheezy
 
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Woosh

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There will always be some area that is subject to some degree of interpretation - such as 'Does the LCD need to be password protected by the suppliers?' - but there is one sure thing, kits are pretty safe as long as people respect the 15mph speed limit.
 
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flecc

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There is nothing on this UK gov site about pre 2016 bikes being ok with a twist and go, they just say they are illegal:


Basically, is this gov site wrong and if it is, when is a pre 2016 e-bike not a pre 2016 e-bike?
Pre January 2016 e-bikes had no law saying they could have throttles, the law merely omitted how the power was controlled, so any method was ok. The EU law once applied meant the power application was only by pedalling.

A pre 2016 e-bike remains a pre 2016 so long as it complies with all of the pre 2016 regulation, in other words, don't "mix and match" in modifying. So to be truly pre 2016 the motor rating should be 200 watts maximum, NOT 250 watts, but a throttle is ok.

I've read the rules for the the original 1983 act and also the update in 2015, but what act applies now?
Both apply to post 2015 e-bikes, the 1983 regulation as modified by the 2015 amendments.

You'll find it much more easy to understand the law if you keep usage and construction separate. For example it's irrelevant to the construction that there's a 14 year old lower age limit, that separate road traffic law just muddies the issue.
.
 

Sturmey

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I've done a couple of conversions using DIY kits and I hope I am ok and following the rules, but the law seems a total mess and is completely confusing.

One is a LCD based Bafang 250W 36V hub drive. All labelled kit etc and should be legit, but...

According to the rules, the ability to change the cut off speed is not allowed by law, eg adding a dongle or having a switch or whatever. The trouble is, all of the LCD systems I've seen can be adjusted to increase the cut off speed. This is because they are mass produced for different jurisdictions, so need to be adaptable. Also, LCD controllers may be fitted to any wheel size, so they need to be adjustable to the wheel you have. This means it's possible to set it up with the wrong wheel size and go faster than the legal limit.

Surely this makes almost all LCD kits on the market technically illegal? (And for that matter, also probably a lot of factory made e-bikes.) Even then, if there isn't an LCD screen on the kit, there can be a significant difference in speed depending on the tyre size used. From a 20-622 to a 60-622 tyre, the circumference difference is more than 10%. This could take you from a max of 15.5 to more than 17 mph (I don't know what the leeway for error is with the 15.5 mph limit).

My other bike is a very old e-bike, which I have updated with a 250W 36V hub motor Voilamart kit (yes, I see you rolling your eyes lol - but it was cheap and I didn't want to spend a lot on this one). It came with a twist and go, so I was wondering if I am still ok legally, if I have updated the bike from a dubious brushed motor and controller, to a modern brushless motor and controller? I know that on this site they talk about bikes made before 2016 being ok to have twist and go, so the bike was legally ok originally, but if it is modified after 2016, is it still ok? I really hate PAS, it is so unnatural and quite frankly dangerous! The last thing I want is my bike to go firing off at full power, just because I've rotated the cranks to change down gear. On my commuting bike I have fitted a "dead man's handle" to the brake sensor, so the motor will not operate unless I am holding the switch down.

There is nothing on this UK gov site about pre 2016 bikes being ok with a twist and go, they just say they are illegal:


Basically, is this gov site wrong and if it is, when is a pre 2016 e-bike not a pre 2016 e-bike?

I've read the rules for the the original 1983 act and also the update in 2015, but what act applies now? I've read we are kind of harmonised with the EU, but we still have our own rules too, like the rider must be over 14. But if EN15194 applies, where does that leave DIY builders, who won't be able to get all their kit CE marked or radio interference tested? Are we only allowed to use e-bikes that have been factory manufactured and signed off as meeting the rules?

Also, is it legal to put a 48V battery on a 250W nominal 36V motor? The law seems to say that the battery voltage needs to be stated, but not that it has to correspond to what is written on the motor! And we all know that a nominal 250W motor is a load of marketing BS. They run at 15Amps x 36 (or up to 42V) during acceleration, so more than double 250W and they can run at this all day long. Are home made battery packs legal? How can they comply with EN15194?

The Voilamart controller comes with wires to override the speed limiting. Do I have to open up the controller and cut them off to make the unit legal? Could I put the controller inside a box and say have a key switch on the outside in order to do the override, would that be legal?

What happens now if someone wants to build their own e-bike from scratch? Eg a recumbent trike or whatever. Is that still allowed?

I know most people using e-bikes have got fed up with the inability of the law to keep up with technology, the market place and the real world and they are just doing what they feel is right, whatever the law says, but an old fart like me does worry about getting caught and getting the book thrown at me (riding an illegal bike without registration, tax, insurance , MOT, helmet etc etc). I know it is extremely unlikely that I would ever get stopped and have my bike checked out for legality, but my worry is if some numpty pedestrian steps out in front of me without taking their eyes off their damn phone and I hit them and injure them and the police start getting interested...

Sorry this is so long and full of questions, but I've had a lot on my mind and this is my first proper post :)

Wheezy
I have attached a copy of EN15194. Its dated 2009 so I'm not sure if its up to date. Anyhow, if you read the document, you will see that the 250W refers to maximum continuous mechanical output power (measured at wheel) and not the electrical input power to motor. There is a complicated graph and formulae used but page 18 clearly shows that the peak power can exceed the continuous power (Pcr)
Page 33 seems to indicate that a speed tolerance or error of 10% is allowed, which makes me think that some of the slower (but more torque) low (201) rpm motors probably would not go much faster than 27.5 Km/hr anyhow.
But anyhow, I may be out of date with this document so please correct me if I am wrong or there are newer regulations or indeed whether this has any bearing at all on the subject.
 

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Nealh

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Tbh as long as your not going overly fast on assisted power or kill/injure someone no one will likely bother.
The guy in London in Feb was cleared of death by dangerous driving on his 1kw ebike come moped over the speed limit.
 

flecc

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Page 33 seems to indicate that a speed tolerance or error of 10% is allowed,
The DfT have confirmed that the UK's own 10% tolerance on all speed limits also applies to e-bike assistance.

So up to 17 mph assisted is ok.
.
 
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Michael Price

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The DfT have confirmed that the UK's own 10% tolerance on all speed limits also applies to e-bike assistance.

So up to 17 mph assisted is ok.
.
Have you a link for that - mine (Bosch)seems to be adjusted a bit high (but below 17) so I would like something official just in case
Thanks
 

sjpt

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I don't think tolerance is meant for explicitly setting outside the defined value; more for accepting that your setting might not be quite right. Either way I think it is unlikely to be an issue with sensible use; as nealh commented above at least on person got off with fragrantly breaking several of the rules and killing someone (though I guess that person had an pretty uncomfortable few months waiting for the trail).
 

flecc

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Have you a link for that - mine (Bosch)seems to be adjusted a bit high (but below 17) so I would like something official just in case
Thanks
It's not online as far as I know, it was an emailed answer in response to the question. Some of us communicated a few times with the DfT during the 2003 to 2013 period when almost all our e-bikes didn't appear to conform to the law.

The answer was quite emphatic though, the 10% applies to all UK speed limits. I daresay it's a practicality issue as much as anything, speed measuring devices of all kinds being imperfect, hence many countries having the same tolerance.

And there are a number of manufactured pedelecs that take advantage of the tolerance. For example some owners of Kalkhoffs with both Impulse and Bosch units have posted that they power to 17 mph and I've owned an Ezee model that also did.

I really don't think you need worry about this.
.
 
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WheezyRider

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Have you a link for that - mine (Bosch)seems to be adjusted a bit high (but below 17) so I would like something official just in case
Thanks
I wouldn't worry Michael. So long as you are under 17, I think you'll be fine. The exact cut out speed will depend on tyre size and also, if you are measuring your speed with a separate speedo, you don't know how accurate that is and how well set up it is.
 
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WheezyRider

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Pre January 2016 e-bikes had no law saying they could have throttles, the law merely omitted how the power was controlled, so any method was ok. The EU law once applied meant the power application was only by pedalling.

A pre 2016 e-bike remains a pre 2016 so long as it complies with all of the pre 2016 regulation, in other words, don't "mix and match" in modifying. So to be truly pre 2016 the motor rating should be 200 watts maximum, NOT 250 watts, but a throttle is ok.



Both apply to post 2015 e-bikes, the 1983 regulation as modified by the 2015 amendments.

You'll find it much more easy to understand the law if you keep usage and construction separate. For example it's irrelevant to the construction that there's a 14 year old lower age limit, that separate road traffic law just muddies the issue.
.

Hope I didn't confuse people with my long post, I've been thinking about a lot of different aspects to this for a long time, so it was a bit of a brain dump

I found this:


But it's not very helpful when it comes to conversion kits and whether they are ok. Also, it states that the act in 2015 is to bring UK law in line with EU law (regulation 168/2013). However, when I read the 2015 act, the only mention of this EU regulation168/2013 is with respect to how motor power output is measured. Am I missing something?
 

WheezyRider

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I have attached a copy of EN15194. Its dated 2009 so I'm not sure if its up to date. Anyhow, if you read the document, you will see that the 250W refers to maximum continuous mechanical output power (measured at wheel) and not the electrical input power to motor. There is a complicated graph and formulae used but page 18 clearly shows that the peak power can exceed the continuous power (Pcr)
Page 33 seems to indicate that a speed tolerance or error of 10% is allowed, which makes me think that some of the slower (but more torque) low (201) rpm motors probably would not go much faster than 27.5 Km/hr anyhow.
But anyhow, I may be out of date with this document so please correct me if I am wrong or there are newer regulations or indeed whether this has any bearing at all on the subject.

Thanks for that, I was struggling to find a PDF of it online. What is interesting in that document is that it is only for 48V. Perhaps that was addressed in a more recent version?

But anyone doing a home build is going to struggle to meet the regs, eg if you build your own battery pack or controller. How can you prove it meets RF interference etc?
 

WheezyRider

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There will always be some area that is subject to some degree of interpretation - such as 'Does the LCD need to be password protected by the suppliers?' - but there is one sure thing, kits are pretty safe as long as people respect the 15mph speed limit.
Like a lot of things here, a total mess and no one cares until it ends up in court and the one with the deepest pockets wins :)

My question remains, if the DoT says that switches/modes or dongles that allow the bike to go over 15.5 mph are illegal, at what level of "barrier to operation" do they consider to be acceptable?

Most LCD controllers don't even need a password, you just go into setup mode. A password is good, but if everyone knows the password, it's pointless.

Is this even something that is mentioned in law, or is it just the opinion of the DoT?
 

flecc

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But it's not very helpful when it comes to conversion kits and whether they are ok. Also, it states that the act in 2015 is to bring UK law in line with EU law (regulation 168/2013). However, when I read the 2015 act, the only mention of this EU regulation168/2013 is with respect to how motor power output is measured. Am I missing something?
No, nothing missing. Where the complexity comes in is in how the issues are dealt with. The UK sometime combined construction and usage into one law, as it did with the 1983 EAPC regulations.

But the EU dealt with them separately for good reasons. The EU deal with construction to allow cross border travel within the EU, and construction is partly dealt with by an exemption in the Two and Three Wheel Type Approval law, currently 168/2013, exemption (h), and mainly dealt with by the EN15194 technical standard.

However, the EU leaves usage to member country governments, and for that we have the usage parts of the 1983 EAPC regulation, as modified 6th April 2015

The conversion kit problem is that there is no construction law of any sort for kits, leaving everyone in the dark. Governments hate vehicle kits, the kit car industry in Europe was destroyed by their laws and it's been severely damaged in the UK too, so it's as well they dont pay attention to our kit motors. All we can practically do with kits is ensure we set them up to comply with our usage laws and trust the authorities know less than us about the subject, which is actually true!
.
 
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flecc

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Thanks for that, I was struggling to find a PDF of it online. What is interesting in that document is that it is only for 48V. Perhaps that was addressed in a more recent version?

But anyone doing a home build is going to struggle to meet the regs, eg if you build your own battery pack or controller. How can you prove it meets RF interference etc?
See my answer above, EN15194 only applies to manufactured bikes, not kits in any way, so attempting to comply isn't valid.
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WheezyRider

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From Cycling UK, an example of the problem with speed setting options with an LCD setup. They are the same people that said that the DoT would not be happy with a system that allowed the 15.5 limit to be subverted and yet here they are promoting such a system:

 
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WheezyRider

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See my answer above, EN15194 only applies to manufactured bikes, not kits in any way, so attempting to comply isn't valid.
.
That's a good way of looking at it :)

I still wonder though, is it ok to put a 48V battery on a "250w" motor with a nominal 36V rating?
 

Woosh

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yes, if you don't derestrict, the motor will be fine.
The problem arises only when people stop respecting the law.
If you ride on a flat road at 15mph, you need less than 200W to maintain your speed. The motor does not use more battery power at 48V than at 36V or 24V to keep you at that speed .
 

flecc

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That's a good way of looking at it :)

I still wonder though, is it ok to put a 48V battery on a "250w" motor with a nominal 36V rating?
As Woosh says. A problem arises if the bike or kit controller doesn't have speed restriction, since a 48 volt battery instead of a 36 volt will increase the assist speed by some 33%, breaking the assist speed law.
.
 

Nealh

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Using a 48v battery is like an instant naughty mode and you can be rding at 25mph with out too much effort not only does the speed increase 33% so does torque which can give great acceleration or a good shove in the back up hills.