Stromer ST5
- Thread starter Timpo
- Start date
Ravi Kempaiah
Well-Known Member
- Region
- Canada
- City
- Halifax
In the US, they are limited to 750W.
JRA
Well-Known Member
There are a few states that have 1000w limits in the law books. Oregon where I live is one of them.
It is kind of a game at this point. Some EU spec 250w bikes can peak at over 600w depending on how they are programmed and a US 750w bike with a 48v battery and a 20amp controller that is a popular option will peak @ 960w. The big thing to me is the speed restriction which is 15.5mph EU and 20mph US and bikes programmed to those restrictions will be only that fast under power, and hard to pedal above that unless on a downhill grade or with a tailwind.
Class III as described by the CA. law and being adopted in other states does allow for 28mph but doesn't address the wattage it takes to get there, but 750w, né 960w even, is not going to maintain that speed unless you are on flat ground with no wind for very long.
It is kind of a game at this point. Some EU spec 250w bikes can peak at over 600w depending on how they are programmed and a US 750w bike with a 48v battery and a 20amp controller that is a popular option will peak @ 960w. The big thing to me is the speed restriction which is 15.5mph EU and 20mph US and bikes programmed to those restrictions will be only that fast under power, and hard to pedal above that unless on a downhill grade or with a tailwind.
Class III as described by the CA. law and being adopted in other states does allow for 28mph but doesn't address the wattage it takes to get there, but 750w, né 960w even, is not going to maintain that speed unless you are on flat ground with no wind for very long.
tomjasz
Well-Known Member
- Region
- USA
- City
- Minnesnowta
To the Federal limit. If it's a programming limit I'd be surprised if someone hasn't defeated it. But I don't expect LEO's to carry multimeters. https://en.wikipedia.org/wiki/Elect...s_Pertaining_to_the_Sale_of_Electric_Bicycles
750w of motor assist on a speed pedelec will allow you to maintain 28mph on flat ground if there isn’t a strong headwind. What more power allows you to do is hold that speed across a wider range of conditions (headwind and\or incline.) Also, as the battery depletes you lose peak power. So with that 20A \ 48v controller you would be down 200w of peak power once the battery voltage drops 10v.
Rooster
Active Member
Yet certain companies in California that are supposed to be all about legal and bad mouth others like Luna, just for example, for building "hotrods," are building bikes that are clearly being ridin on streets and paths in excess of 30 mph and built to do so. These bikes are clearly advertised as "1000 watts ", 34 mph, etc in the U.S. and people are clearly abusing this law. How long do you think this will be good for the ebike industry? I'm sure the same people worked very hard to get the class 3 law passed only to challenge it. Something is wrong with that picture and I understand the "off road mode "but everyone knows that is just a loophole and it will inevitably be abused. Just a matter of time before someone hurts their self or worse, someone else and then what. Motorcycles with pedals. These people act all dedicated to the cause but all their dedicated to is their pockets. And you know who you are.
Rooster
Active Member
I don't know what planet your from but I beg to differ, it takes at least 1000 watts maybe 950 to get 28 mph on flats with no wind and that is tested true. I'm talking 750 watts peak power, not gonna happen.
michael mitchell
Member
I think we have to look at other factors once you get above about 25mph. For example, on my 350 watt bike, I can maintain 27-28 for as long as the road stays straight, smooth, and flat and the battery is above a certain threshold. Around me (Seattle area), the straightest, smothest road is about 1/2 mile near an airport. I certainly have to work, but it's possible without me going into the red. I'm also fairly thin, and I often ride an unpowered road bike as well.
So, you'd need to factor in rider variables (weight, clothing and helmet type, seating position, power output/fitness, cadence). Plus bike variables (weight, design aerodynamics, tire type/pressure, luggage/no luggage), and environment variables (wind, gradient, terrain type).
It's more than strictly nominal and peak watts. Otherwise, the Specialized Turbo S wouldn't hit 28 either. That's 500/750 I believe.
I come from a road cycling background and I ride with a power meter on my road bikes (which very accurately measure rider power). I am pretty familiar with how much power it takes to maintain 28mph on flat ground with no wind. It’s around 400-500 watts on a road bike (depending on rider size and position.) Add in the less efficient position and heavier weight of an e-bike and you’re looking at 600-700 watts. And don’t forget that the rider is adding to the motor power so it’s very doable on a street legal speed pedelec in the right conditions.
Rooster
Active Member
Your right, it's possible but your working your ass off and watts aren't just about your motor, it's about your battery and controller, volts and amps and I too have a power meter, that's a must have for efficiency and if you're athletic enough you can do it with no motor on the right bike. That just didn't come out right, my bad.
JRA
Well-Known Member
This is my best effort to date.
This was from last summer, flat 2 lane paved country road with little to no wind. The trick is to have high enough gearing to be pedaling effectively at a cadence you can maintain along with a strong motor. Average was 1000w and 30 wh/mi. That is the other trick, getting your battery to last very long trying to maintain speeds over 23 mph +/-, dealing with wind, hills.....and as mentioned so many other variables.
This was from last summer, flat 2 lane paved country road with little to no wind. The trick is to have high enough gearing to be pedaling effectively at a cadence you can maintain along with a strong motor. Average was 1000w and 30 wh/mi. That is the other trick, getting your battery to last very long trying to maintain speeds over 23 mph +/-, dealing with wind, hills.....and as mentioned so many other variables.
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