Why does every eBike seem to advertise a 20-30 mile range?

[Swytch Bike]

There is a big issue in the marketplace at the moment that eBike manufacturers and sellers are all over the place about what range they quote on their eBike. There is no authority on what is a sensible way to estimate range, and so people are saying whatever range they feel suits their sales strategy...

Internationally trusted source Forbes quotes the Espin eBike which has a 418Wh battery as having a 30 miles range.
Link: Forbes says that about 400Wh = 30 miles

Meanwhile, companies selling eBike kits and eBikes that have small batteries, such as the UrbanX (which has a 125 Wh battery) are also quoting a 30 mile range:

Link: Treehugger says that about 100Wh = 30 miles

Who is right?

Please comment with your suggestions and take part in the poll

As a side note, we never tell customers the range in miles. We always quote the range in hours , because we can accurately estimate your range in hours, depending on how hard you are driving the motor.

See here for our blog on this topic: How much range will i get?
https://www.pandaebikes.com/much-range-will-get/
PANDA EBIKES BLOG - HOW MUCH RANGE WILL I GET?
We can't tell you your range in miles, but we can tell you your range in hours!

 

[Woosh]

they can of course be all correct and all incorrect.
These ranges are estimates and the companies should make that very clear and also give the WH or at least AH which are better approximation of the capability of their batteries.

 

[flecc]

Why does every eBike seem to advertise a 20-30 mile range?

It's the distance covered in the two hours to the first breakdown.
.

.

 

[Deleted member 4366]

A rider who's 100kg will use approximately 1.7 times the power of a rider who is 50 kg, so, on the same journey and the same bike, if the 100kg rider got 30 miles, then the 50kg one would get 51 miles.

On my own bike, if I'm in a hurry ot lazy, I can empty the battery in 20 miles. On the other hand, if I ride for exercise, my record is 179 miles.

Any statement that anybody makes about the range of their own bike or any other one is completely meaningless because it's specific to themselves, and the way they ride. It really annoys me when people come on here saying how great their bike is because it can do 100 miles, and they don't give any qualifying information, which is very misleading to the average overweight unfit new members, who would be very disappointed when they buy the same bike and find that they struggle for 20 miles range.

Similar to the guy the other day, who was saying to a 100kg prospective ebike buyer how great his bike was on the hills, but forgot to mention that he only weighed 50kg himself!. The 100kg rider would need approximately 1.7 times the amount of power to get up the same hill. so if the 50kg rider goes up on full power with the standard 15 amps, the 100kg rider, to go up with the same effort at the same speed, would need 25.5 amps, which is not available on any legal OEM bike (AFAIK).

Coming back to the question. An average 90kg rider, who's not particularly fit, but wants to get fit by putting in a bit of effort, and who has hills in his rides (normal reason for wanting an ebike), would get something like 30 miles per 360 watt-hours or would use about 12 watt-hours per mile. There's no magic formula for range in any bike. It's just a question of battery size. The only exception is when you travel fast, a slim, lightweight bike with lower resistance will be more efficient than something like an MTB with knobbly tyres, and worst of all will be a fat-bike.

 

[Swytch Bike]

Agreed that Ah or Wh are the right approximations to use, but too many people find these confusing hence why so many companies are going for "you get X miles of range" because it is a measure that people can identify with.

But with so many companies quoting essentially the same range for totally different bikes, there should be a kind of basic standard out there that helps to avoid misinformation.

D8veh - everything you're saying is totally spot on. Don't you think though that the quoting of 20-30miles range by every eBike seller regardless of battery capacity needs to be reined in? Any suggestions as to what is a fair middle ground for what range is fair to quote for a certain Wh capacity? Certainly, the range of a 400Wh battery should be roughly 4x that of a 100Wh battery.

Maybe there should be a lazy-energetic range, e.g. 100Wh = 5-15 miles (lazy-energetic) and 400Wh should be 20-60 miles. So that customers are always given a range of ranges - it can't remain the case that range is always quoted as one single number that is the same for all eBikes because it is quite confusing to the end consumer.

 

[anotherkiwi]

I agree d8veh which is why when I was posting my range related posts I always posted the ride profile.

D8veh - everything you're saying is totally spot on. Don't you think though that the quoting of 20-30miles range by every eBike seller regardless of battery capacity needs to be reined in? Any suggestions as to what is a fair middle ground for what range is fair to quote for a certain Wh capacity? Certainly, the range of a 400Wh battery should be roughly 4x that of a 100Wh battery.

Maybe there should be a lazy-energetic range, e.g. 100Wh = 5-15 miles (lazy-energetic) and 400Wh should be 20-60 miles. So that customers are always given a range of ranges - it can't remain the case that range is always quoted as one single number that is the same for all eBikes because it is quite confusing to the end consumer.

Bosch have a fair go with their web range calculator. As to your original Panda, question it is just marketing. I think that after a spate of saying that their bikes could do unreasonable ranges and then getting negative feedback from buyers they are just playing their cards close to the chest, not taking any risks.

 

[Fish2]

Close to worst case range should be advertised.
And there would be a lot of happy customers

 

[Woosh]

I usually ask the customers where they live, then give then my estimate the range that they can expect. The mental arithmetics works like this:
small motor (Bafang SWX): 10WH per mile
medium size motor (Bafang SWX02): 11WH per mile
big motor and CD motor: 12WH per mile
weight factor: 0.5WH per stone over 12st
Terrain factor: hilly: add 1WH per mile, very hilly: add 2WH per mile
can't pedal much factor: add 2WH per mile.
Like going fast factor: add 1WH per mile.

So for somebody like Kangooroo, not wanting to go fast, and her bike has a small motor (7st, hilly, small motor), it works out to 10 (small motor) +1 (hilly) - 3 (weight) = 8WH per mile.
For somebody like d8veh on a Big Bear (15st, hilly, large motor, like going fast), it should be 12 (big motor) + 1 (hilly) + 2 (weight) + 1 (going fast) = 16WH per mile.

I would then tell the customer: your battery has x WH, I reckon you can do x/y miles on a full charge but be careful, leave some margin if you tire easily.

 

[Deleted member 4366]

Woosh's formula looks about right, but you couldn't put that in an advert.

The main problem is that it's an obvious question that anybody asks, but the answer is too complicated to be easily understood. The worst thing is that people take the publicised ranges as definitive.

I don't think you can make a standard test to compare different systems because there's too many variables. whatever procedure you come up with. it'll favour some systems more than others.

The best test I've seen was when a German magazine tested a range of bikes by riding them up a mountain until each conked out. The results were surprising, when the hub-motors proved to be more efficient and better climbers than the crank-drives. Did they put the lightest riders on the hub-motored bikes? Obviously, if they did the test down the mountain, they'd have got totally different results.

 

[Woosh]

The results were surprising, when the hub-motors proved to be more efficient and better climbers than the crank-drives.

How about this as an explanation:
the rider on the bike with a hub motor may have chosen a gear that suits his natural cadence and sticks to it, he is therefore more productive pedaling his bike than his mates who have to change gears all the time.

 

[Danidl]

I usually ask the customers where they live, then give then my estimate the range that they can expect. The mental arithmetics works like this:
small motor (Bafang SWX): 10WH per mile
medium size motor (Bafang SWX02): 11WH per mile
big motor and CD motor: 12WH per mile
weight factor: 0.5WH per stone over 12st
Terrain factor: hilly: add 1WH per mile, very hilly: add 2WH per mile
can't pedal much factor: add 2WH per mile.
Like going fast factor: add 1WH per mile.

So for somebody like Kangooroo, not wanting to go fast, and her bike has a small motor (7st, hilly, small motor), it works out to 10 (small motor) +1 (hilly) - 3 (weight) = 8WH per mile.
For somebody like d8veh on a Big Bear (15st, hilly, large motor, like going fast), it should be 12 (big motor) + 1 (hilly) + 2 (weight) + 1 (going fast) = 16WH per mile.

I would then tell the customer: your battery has x WH, I reckon you can do x/y miles on a full charge but be careful, leave some margin if you tire easily.

.... Ok but ignoring wind resistance. A stiff breeze can half or double range depending on direction. ...

 

[Swytch Bike]

I once worked at the Jaguar Land Rover hybrid vehicles department. For Electric Cars, drive cycles under specific conditions are used to determine the range that can be declared, and it is regulated to a certain extent.

The eBike industry is growing and will not be so many years before it is comparable to the car industry. Surely this problem needs to be solved with a similar kind of "drive cycle" process, with 3rd party companies verifying for the main brands what kind of range figure is actually fair to advertise

 

[Fish2]

Indeed! So we don't end up with a test similarly stupid as NEDC is for cars

 

[Danidl]

How about this as an explanation:
the rider on the bike with a hub motor may have chosen a gear that suits his natural cadence and sticks to it, he is therefore more productive pedaling his bike than his mates who have to change gears all the time.

... Changing gears all the time? Don't get that. The purpose of selecting a gear is to get a cadence and pressure which suits the rider, , The crank drive then matches that, and will should be running at close to its peak efficiency. I find that gear changing on the cd ebike very quick, and that I don't need the range I would have needed on a manual bike

I would assume that if the rider had suceeded in getting their bike speed to the peak efficiency part of the power curve on a hub motor, it will have the edge in efficiency, but with probably more effort from the rider.

 

[Woosh]

The purpose of selecting a gear is to get a cadence and pressure which suits the rider.

The test in d8veh's post is hill climbing. For a CD motor climbing a hill, you need to select a gear that suits the motor + gradient combo for the best climbing speed. The guy who rides a hub bike is not so constraint, he is freer to choose.

 

[Danidl]

they can of course be all correct and all incorrect.
These ranges are estimates and the companies should make that very clear and also give the WH or at least AH which are better approximation of the capability of their batteries.

... The better of these would be watthr , as it would equate accross technologies.

 

[Woosh]

some factors affecting the average range beside the weather that I can think of:

1. tyre width and diameter
2. tyre inflation pressure
3. quality of the suspension and its setting
4. traffic
5. Clothing
6. type of motor, some are truly awful at start/stops, some too good at it and subsequently wasting energy.

 

[mike killay]

Some years ago I rode back and fore along the Swansea cycle path which is flat. There was not any wind.
I did not pedal at all.
I got 17 miles from a 360 watt/H battery

 

[Deleted member 4366]

Clothing can make a massive difference. You can really feel the difference between lycra and jeans on a road-bike. I can understand why the top racers shave their legs. Wind tunnel tests showed an advantage of 70 seconds over 40 km and another 11 seconds for shaving your arms.

 

[IR772]

This is easily settled on a Pan European basis and now is a good time to get it going.

All the manufactures and importers hand their products over for range testing to an independent trustworthy organisation who could set up a standard for us all to follow. I would recommend Volkswagen as they have a lot of experience in this field.