Limiting power down to legal levels

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d8veh   100 GW

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Re: Limiting power down to legal levels

Post by d8veh » Oct 01 2017 6:48am

There is no power limit specified in EN 15194, so there's no test you can do to verify that it complies. The only requirement is that your have a 250w motor (max), so the only test they can do is check the motor label. To comply with EN 15194, your bike must have a label that says that the motor is rated at 250w, the name of the manufacturer and the maximum speed.

The old rule in Austrslia was a maximum output power of 200w, which could easily be tested, but I bet not a single bike sold with a 200w label would pass that test as that would require a controller limited to around to around 7 amps max at 36v or 10 amps at 24v, both of which would be absolutely useless.

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Re: Limiting power down to legal levels

Post by barbs00 » Oct 01 2017 7:22am

e-beach wrote:An inexpensive liner taper potentiometer spliced into the return wire (often the white wire) from your throttle will do the trick. No amp problems doing it that way. One side of the wire to an outside post, the other side to the middle post. Play with it until you find the setting that works for you.

:D
Cheers!
Something like this?

https://www.aliexpress.com/item/Free-sh ... 38c4b5545f

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Re: Limiting power down to legal levels

Post by barbs00 » Oct 01 2017 7:37am

d8veh wrote:There is no power limit specified in EN 15194, so there's no test you can do to verify that it complies. The only requirement is that your have a 250w motor (max), so the only test they can do is check the motor label. To comply with EN 15194, your bike must have a label that says that the motor is rated at 250w, the name of the manufacturer and the maximum speed.

The old rule in Austrslia was a maximum output power of 200w, which could easily be tested, but I bet not a single bike sold with a 200w label would pass that test as that would require a controller limited to around to around 7 amps max at 36v or 10 amps at 24v, both of which would be absolutely useless.
It seems what the legislation says and how it is enforced are different things. From my understanding now:

1. As long as you have a 200w( throttle) or 250w( no throttle) you can put as much juice as you want through the motor. (Seems kinda crazy but hey)

2. However, should the cops pull you over they could take your bike and test the power at the back wheel, if you are over the legal limit then you get fined.

Perhaps you could win in court if you had a 250w motor generating 500w at the back wheel ?
If you were going close to 25km/h the 250w sticker may be enough but obviously if you are going 50km/h you are probably going to get tested and will have to fight your case.

3. For those of us with motors over the limit (not many I am sure :wink: ) it is good to know that we can limit our power down and pass an engineers test and probably get off even though technically according to EN15194 we cannot have a motor over 200w/250w.

Some discrepancy between the law and how the cops enforce things ! Who would have thought....Not in Australia!

If this shit keeps up we will soon need a license to own a water pistol!

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Re: Limiting power down to legal levels

Post by e-beach » Oct 01 2017 10:16am

Yea something like that. If trimmed down, is will simply cut the return from about 5v when WOT to something less there-by reducing the throttle signal to your controller and keeping the amps from your motor. A three position switch will do the same, but they have set positions. If that kind of a setup works for your local police then here is a picture showing the wiring I was referring to.
100k pot.JPG
100k pot.JPG (160.77 KiB) Viewed 2582 times
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KINNINVIEKID   1 kW

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Re: Limiting power down to legal levels

Post by KINNINVIEKID » Oct 01 2017 1:31pm

barbs00 wrote:
Thanks, So you can't just press a button or 2 and switch between power levels?
No,you have to unplug the LCD then plug the box in.
My plan if I get stopped is to turn the motor off then tell them I have to plug the precharge box in before I can start the motor.
Can't see anyone who would know what i was really doing.
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Re: Limiting power down to legal levels

Post by barbs00 » Oct 01 2017 4:20pm

KINNINVIEKID wrote:
barbs00 wrote:
Thanks, So you can't just press a button or 2 and switch between power levels?
No,you have to unplug the LCD then plug the box in.
My plan if I get stopped is to turn the motor off then tell them I have to plug the precharge box in before I can start the motor.
Can't see anyone who would know what i was really doing.
Good to know - thanks!

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Re: Limiting power down to legal levels

Post by barbs00 » Oct 01 2017 4:21pm

e-beach wrote:Yea something like that. If trimmed down, is will simply cut the return from about 5v when WOT to something less there-by reducing the throttle signal to your controller and keeping the amps from your motor. A three position switch will do the same, but they have set positions. If that kind of a setup works for your local police then here is a picture showing the wiring I was referring to.
100k pot.JPG
Lovely - thanks!

Will this work for the PAS also?

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Re: Limiting power down to legal levels

Post by e-beach » Oct 01 2017 9:12pm

barbs00 wrote:......Will this work for the PAS also?
If you are asking "Will the pas work with a pot inline on the return voltage of the throttle?" The answer is yes because they are on different circuits on your controller.

:D
Favorite Quote: "This is L.A., sugar. There is no 'over the top." --- Chris Erskine

Current build: Liahona w/ cheap front suspension and suspension seat post. Yescomusa 36v 800w generic front hub motor. 15ah Headway triangle mounted pack. Tronsung 30 amp,

Previous Build:1992 Trek Antelope 800 - Bone Crusher (no suspension) - Yescomusa 800 watt 36 volt front wheel kit. Don't do it! Get suspension!!!

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Re: Limiting power down to legal levels

Post by dustNbone » Oct 01 2017 10:07pm

I was thinking a bluetooth enabled controller that you can set default power level on for when the controller is first turned on. If you want to increase the power, you need to use an app on your phone to set a higher amp limit.

So you get pulled over, you turn off the bike. If the cops take it and turn it back on they get 10A or whatever you set the default to.

They give you back your bike and they go away, you pull out your phone and make your bike fun again.

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Re: Limiting power down to legal levels

Post by barbs00 » Oct 02 2017 3:00am

e-beach wrote:
barbs00 wrote:......Will this work for the PAS also?
If you are asking "Will the pas work with a pot inline on the return voltage of the throttle?" The answer is yes because they are on different circuits on your controller.

:D
Yes - I should have been more clear :D

I guess what I meant to ask was will adding the pot inline on the return voltage of the throttle also limit the PAS to 200/250w or whatever you set it to?

I guess the answer is no since they are on different circuits?

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Re: Limiting power down to legal levels

Post by barbs00 » Oct 02 2017 3:02am

dustNbone wrote:I was thinking a bluetooth enabled controller that you can set default power level on for when the controller is first turned on. If you want to increase the power, you need to use an app on your phone to set a higher amp limit.

So you get pulled over, you turn off the bike. If the cops take it and turn it back on they get 10A or whatever you set the default to.

They give you back your bike and they go away, you pull out your phone and make your bike fun again.
Yes I think this a a great option

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Re: Limiting power down to legal levels

Post by tommie » Oct 02 2017 5:44am

barbs00 wrote:
e-beach wrote:
barbs00 wrote:......Will this work for the PAS also?
If you are asking "Will the pas work with a pot inline on the return voltage of the throttle?" The answer is yes because they are on different circuits on your controller.

:D
Yes - I should have been more clear :D

I guess what I meant to ask was will adding the pot inline on the return voltage of the throttle also limit the PAS to 200/250w or whatever you set it to?

I guess the answer is no since they are on different circuits?
Isn`t that what the EggRider is all about?

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Re: Limiting power down to legal levels

Post by barbs00 » Oct 02 2017 6:02am

Yeah Tommie - the eggrider app will do it although it is not available yet. This way is easy and cheap though!

I am still waiting on a reply email from them.

I think the Bafang controller will remember the last setting you had in should you unplug the LCD. So hopefully if you are in street legal mode and the cops take your bike (and you keep your phone) it should pass testing. Not 100% on this - I hope the egg guys answer soon.

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Re: Limiting power down to legal levels

Post by tommie » Oct 02 2017 7:57am

Re Eggrider?

Did they run out of money?

https://www.kickstarter.com/projects/60 ... ref=7qqv6b

£820 pledged of £10,000 goal
15
backers
Funding Unsuccessful
This project's funding goal was not reached on May 4.

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Re: Limiting power down to legal levels

Post by barbs00 » Oct 03 2017 5:39am

Interesting!

Still no reply from them...maybe they are finito ?

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Re: Limiting power down to legal levels

Post by SaladFish » Oct 03 2017 7:30am

How about using a creatively hidden reed switch to activate full power using a hidden magnet on your person?



Blue tooth activation would also be good. Perhaps a code could be sent by your phone to the controller each time you turn the bike on.

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Re: Limiting power down to legal levels

Post by e-beach » Oct 03 2017 9:50am

Reed switch.....hmmmm. They are delicate but it could be done simply. Say one puts a resistor inline on the return wire from their throttle. The resistor will hard limit the throttle return voltage. However if a reed switch is placed so that when it turns on, via a magnet, it jumps the resistor and the throttle could go full throttle, it could work.

:D
Favorite Quote: "This is L.A., sugar. There is no 'over the top." --- Chris Erskine

Current build: Liahona w/ cheap front suspension and suspension seat post. Yescomusa 36v 800w generic front hub motor. 15ah Headway triangle mounted pack. Tronsung 30 amp,

Previous Build:1992 Trek Antelope 800 - Bone Crusher (no suspension) - Yescomusa 800 watt 36 volt front wheel kit. Don't do it! Get suspension!!!

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Re: Limiting power down to legal levels

Post by barbs00 » Oct 04 2017 5:44am

Ha, Sneaky....I like it!

The only issue it it won't limit the PAS so you may not pass a test

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Re: Limiting power down to legal levels

Post by izeman » Oct 04 2017 9:03am

i'm wondering when ppl will start to understand that there is no "200W rated" motor. the BIKE can be rated 200W, but not the motor alone. it's the combination of motor, controller and battery that determines how much power the rear wheel will see. an electric motor per se can take unlimited power for a very short period of time. putting a 15kg DD drive in your rear wheel, adding a 36V lead acid battery and a 250W (7A battery current limited, 25km/h) controller will give you a perfectly legal 250W bike.

and therefor i doubt that any legislation anywhere around the world has any other way to determine the bike's power, but to put the bike on a dyno. easy as that.
would a "250W" sticker fool anyone? maybe yes, probably not. would a legally (250W) crippled bike become illegal if you put a "1000W" sticker on it? no way.
you can put rally strips on your car, and it will not become more powerful just by the "agressive" look it has.

so the only way to deal with it, is some kind of hidden switch. it depends on the time the engineer, who checks the bike, is willing to spend, to find the switch. adding a BT device, hidden in the motor controller, or a reed switch inside the handle bar, that gets activated once you touch it with your "magnet added" gloves, may be a good way. but it can be found if looked for it long enough.

the only save way would be to "destroy" the controller cpu/mcu so it can't be tested. no way to tell what the bike was capable of at the time you rode it.

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Re: Limiting power down to legal levels

Post by wturber » Oct 04 2017 10:23am

izeman wrote:i'm wondering when ppl will start to understand that there is no "200W rated" motor. the BIKE can be rated 200W, but not the motor alone. it's the combination of motor, controller and battery that determines how much power the rear wheel will see. an electric motor per se can take unlimited power for a very short period of time. putting a 15kg DD drive in your rear wheel, adding a 36V lead acid battery and a 250W (7A battery current limited, 25km/h) controller will give you a perfectly legal 250W bike.

and therefor i doubt that any legislation anywhere around the world has any other way to determine the bike's power, but to put the bike on a dyno. easy as that.
would a "250W" sticker fool anyone? maybe yes, probably not. would a legally (250W) crippled bike become illegal if you put a "1000W" sticker on it? no way.
you can put rally strips on your car, and it will not become more powerful just by the "agressive" look it has.

so the only way to deal with it, is some kind of hidden switch. it depends on the time the engineer, who checks the bike, is willing to spend, to find the switch. adding a BT device, hidden in the motor controller, or a reed switch inside the handle bar, that gets activated once you touch it with your "magnet added" gloves, may be a good way. but it can be found if looked for it long enough.

the only save way would be to "destroy" the controller cpu/mcu so it can't be tested. no way to tell what the bike was capable of at the time you rode it.
But the issues is probably more likely one of simply dealing with a LEO. In that case, a "1000W" sticker may get you a citation and a "250W" sticker may help you avoid one. Appearances matter. I've read the accounts here in Phoenix of e-bikes getting cited because the "e-bike" is a commercial product that looks like a moped. In our neck of the woods, it appears that I can break our current laws (can't go past 20mph or else you are a MoPed and require registration and I think insurance) with regularly if I appear to be a more or less "regular" bike and don't ride at high speeds in a way that is likely to attract attention. OTOH, I can be perfectly within the law and get hassled regularly if my appearances are confusing to LEO. Appearances seem to matter.

So in the end what is important is to understand what the LEOs in your area are likely to do. That will inform you of what you can get away with and what you probably need to do so that you are likely to be considered compliant - whether you are compliant or not.

Personally, I think the laws based on motor power and speed capability are wrong-minded. I think speed limit based laws make much more sense. It is an area that LEOs should be relatively comfortable judging and it tries to regulate behavior, which is probably more important when it comes to safety, traffic flow, and the interaction of pedestrians, bikes, e-bikes and motor vehicles. After all, cars are routinely registered that have motors capable of travelling well past legal limits in the majority of locations. The cars are perfectly legal. What matters most is how they are operated. A similar approach should, IMO, be adopted for e-bikes. Any power limit set should be well above what is needed to operate at allowable speeds - probably 2-3 times the power generally required for a given speed. That will allow the e-bikes the ability to deal with wind and hills and to accelerate reasonably to get to their legal speed limits.
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Re: Limiting power down to legal levels

Post by izeman » Oct 04 2017 1:47pm

i agree. fake pedaling, and slowing down in crowded areas, looking behind you once and then to check for cops is a clever idea.
i was talking about a "real" check. putting a 250W sticker may help in case a cop sees your parked bike somewhere and is just over busy. if all looks ok from a first sight they may let you go 90% of the time.
if you are unlucky enough to have an accident (maybe with human casualties) the will double check your bike. therefore your pre cautions can't be good enough.

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Re: Limiting power down to legal levels

Post by dustNbone » Oct 04 2017 2:43pm

I'm not sure restricting the throttle input on most controllers will help pass a dyno test anyway, as most of them are "Speed" controls rather than "Current" controls. You can restrict the speed setting by using a pot/inline resistor with switch, etc but the controller will still apply whatever current it's set for to attain that (lower) speed. So putting it on a dyno and hitting the throttle will likely still measure too high of a wattage.

If you can set the controller to "current" throttle mode (which the Bafang is capable of, but usually not set to by default), and calibrate your restrictor correctly, this method may work, but setting the controller itself to a lower (legal) amp limit on power up seems more reliable to me. Doing it with bluetooth eliminates the possibility of your "hidden" switch/pot being discovered.

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Re: Limiting power down to legal levels

Post by wturber » Oct 04 2017 3:18pm

izeman wrote: if you are unlucky enough to have an accident (maybe with human casualties) the will double check your bike. therefore your pre cautions can't be good enough.
Agreed. Being involved in an accident is a whole different thing. I guess I wasn't even thinking that way because the last car/bike accident I had was when I was 12 and door-posted a VW bug that passed me and turned right directly in front of me. The driver lost a chrome trim strip off her door and I learned a lesson about automobile drivers. Since then, no such accidents or even close calls really (discounting drivers that pass too closely.)
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Re: Limiting power down to legal levels

Post by wturber » Oct 04 2017 10:19pm

e-beach wrote:Reed switch.....hmmmm. They are delicate but it could be done simply. Say one puts a resistor inline on the return wire from their throttle. The resistor will hard limit the throttle return voltage. However if a reed switch is placed so that when it turns on, via a magnet, it jumps the resistor and the throttle could go full throttle, it could work.

:D
It is slightly more complicated but quite a bit more durable to do the same thing with a hall effect sensor.
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
8 x 36v 4.3ah 10s 2P battery packs - 1500W 30A DC Boost Converter delivers 54v and about 1000 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
viewtopic.php?f=2&t=90369

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Re: Limiting power down to legal levels

Post by d8veh » Oct 05 2017 5:11am

izeman wrote:i'm wondering when ppl will start to understand that there is no "200W rated" motor. the BIKE can be rated 200W, but not the motor alone. it's the combination of motor, controller and battery that determines how much power the rear wheel will see.
We all understand what "rated power" means. What people misunderstand is how it applies to the regulations.

The motor always has a rated power. It's often stamped or labelled on the motor. The 200w limit in Australia is not rated power, it's maximum output power. In UK, the 200w limit was indeed rated power, the same as it is now, but now 250w.

The only power regulation in EN 15194, which is the standard that applies in Australia, Europe and some other countries, is on the "rated" power of the motor. You're correct that it has no bearing on the power of the bike, but there's no regulation on how much power the bike uses or produces. That means that it doesn't matter what shows on any dyno because every power is allowed. We can argue all day about why it's like that, but that's how it is, fortunately.

There's also a limit on voltage specified. It says "up to 48v", but that is also very specific. Does it mean up to a 48v system that can go to 54v, or does it mean 48v absolute limit, so 11S max?

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