Why ebikes are good / bad

[Bunged Knee]

For someone who wants to research ebikes for info and estimate price guide.

https://www.canstarblue.com.au/vehicles ... australia/

[Janice]

https://www.bikeexchange.com.au/blog/e- ... nd-reviews

Good information

[Janice]

I sent a letter to the Minister for Roads asking for s pedelecs to be legalised. Not expecting much though.

[Comedian]

I sent a letter to the Minister for Roads asking for s pedelecs to be legalised. Not expecting much though.

What state are you?

[Janice]

What state are you?

NSW

[Janice]

https://www.bicycling.com/news/a3298436 ... e%20budget.

New York City allows ebikes up to 40km/h no rego or licence required.

[Comedian]

https://www.bicycling.com/news/a3298436 ... e%20budget.

New York City allows ebikes up to 40km/h no rego or licence required.

Interesting.. thanks for sharing.

You might enjoy this video. A moderately famous tech youtuber riding around NYC. It's a hostile environment. Personally I rarely see the hotted up e-bikers on the road.. actually I rarely see any e-bikers on the road.. they seem to prefer to stick to bike paths. If people riding higher powered e-bikes were prepared to stay off bike paths I think I'd personally be supportive. But from what I've seen I don't think they would. I think they would rather be king of the bike path than a minnow amongst the sharks on the road. Perhaps if it was legal behaviours would be different though.

https://www.youtube.com/watch?v=sCNqodl5uQY

[Mr Purple]

Interesting discussion in here, good to see the view points of the other side!

As a naturally aspirated cyclist the only time I really have any issues with e-bikes is when they're ridiculously overpowered and ridden by someone who clearly has no idea what they're doing.

That would be the difference between having a speed limit on e-bikes and not on normal bicycles - I can be fairly sure if I'm drafting an unassisted cyclist at 40+km/hr that they've done a lot of miles, and a lot of training, to get there and have a fair idea what they're doing. To get an illegal e-bike to those speeds you literally just need a few grand and a disregard for the law.

Having said that the vast majority of e-bikers I see, even the ones riding derestricted - are fairly sensible and moderate in their approach. Though I distinctly remember being passed on at least two occasions by guys on flatbar roadbikes doing 50km/hr+ on the flat while not pedalling at all. Both looked like they were about to spear into the river at any second.

Anyway, I agree the 25km/hr limit is too low. Bring it to 30km/hr and you'll probably have fewer illegal bikes and make the whole thing safer. As it stands someone is going to kill themselves in a particularly stupid way and unfortunately probably get ALL e-bikes banned in a government overreaction.

Anyone who rides an electric scooter down the wrong side of a bikeway while texting though? Those guys should be summarily executed.

[Comedian]

Interesting discussion in here, good to see the view points of the other side!

As a naturally aspirated cyclist the only time I really have any issues with e-bikes is when they're ridiculously overpowered and ridden by someone who clearly has no idea what they're doing.

That would be the difference between having a speed limit on e-bikes and not on normal bicycles - I can be fairly sure if I'm drafting an unassisted cyclist at 40+km/hr that they've done a lot of miles, and a lot of training, to get there and have a fair idea what they're doing. To get an illegal e-bike to those speeds you literally just need a few grand and a disregard for the law.

Having said that the vast majority of e-bikers I see, even the ones riding derestricted - are fairly sensible and moderate in their approach. Though I distinctly remember being passed on at least two occasions by guys on flatbar roadbikes doing 50km/hr+ on the flat while not pedalling at all. Both looked like they were about to spear into the river at any second.

Anyway, I agree the 25km/hr limit is too low. Bring it to 30km/hr and you'll probably have fewer illegal bikes and make the whole thing safer. As it stands someone is going to kill themselves in a particularly stupid way and unfortunately probably get ALL e-bikes banned in a government overreaction.

Anyone who rides an electric scooter down the wrong side of a bikeway while texting though? Those guys should be summarily executed.

See the other thread "Are e-bikes yesterdays trend" or something like that. As a follower of this.. hotting e-bikes is fading IMHO. It's much easier and cheaper to buy a scooter for $2500 and remove the limiter. They are faster than an e-bike and no need for that tawdry pedalling.

I suggest if you want to observe the state of things hang out where I do my bike counts. It's at the top of a rise so you can see cresting speed easily from both directions. It's the big scooters that are the fastest. You can usually pick them by the full face helmets. Mind you I saw a guy on a mono wheel doing around the 40 last week. What can possibly go wrong!

Thing is they tend to be commuter focused so I can't imagine you seeing them on cootha trying to steal KOM/QOMs.

[Mr Purple]

Are you counting on the bike paths? I take the veloway for most of my training rides - on weekends it's pretty much all bikes, but on a weekday you can definitely see a large number of scooter riders in their work clothes.

I find most of the commuters sensible and agree it's a fantastic way to commute given their portability and availability.

I have been passed by guys on scooters at speed while climbing Cootha, too, but only the once! That seems a bit of a bizarre thing to be doing and I don't think the descent would be particularly safe or interesting for them. I don't imagine any of the scooter riders would be using Strava anyway so that's not an issue.

Again I don't think it's particularly safe to have scooters doing 40km/hr+ on our bikeways. A lot of them have no experience, little control, aren't concentrating particularly well and to top it off they have those little wheels that aren't particularly good for stopping, going around corners or providing stability. Though I do agree the 25km/hr limit is too slow, 30 would be fine and probably lead to less flagrant abuse of the restrictors.

[Comedian]

Are you counting on the bike paths? I take the veloway for most of my training rides - on weekends it's pretty much all bikes, but on a weekday you can definitely see a large number of scooter riders in their work clothes.

I find most of the commuters sensible and agree it's a fantastic way to commute given their portability and availability.

I have been passed by guys on scooters at speed while climbing Cootha, too, but only the once! That seems a bit of a bizarre thing to be doing and I don't think the descent would be particularly safe or interesting for them. I don't imagine any of the scooter riders would be using Strava anyway so that's not an issue.

Again I don't think it's particularly safe to have scooters doing 40km/hr+ on our bikeways. A lot of them have no experience, little control, aren't concentrating particularly well and to top it off they have those little wheels that aren't particularly good for stopping, going around corners or providing stability. Though I do agree the 25km/hr limit is too slow, 30 would be fine and probably lead to less flagrant abuse of the restrictors.

I do my counts on the bicentennial bikeway, on a Thursday in good weather between 4:30 and 5:30. My intention is to count commuters and log the breakdown of vehicles. When I started I tried counting in the morning but it was a completely different demographic.. lots of roadies returning from their sport rides - so I switched to the afternoons to get rid of that noise in the counts.

[Janice]

https://www.bicycling.com/news/a3298436 ... e%20budget.

New York City allows ebikes up to 40km/h no rego or licence required.

Interesting.. thanks for sharing.

You might enjoy this video. A moderately famous tech youtuber riding around NYC. It's a hostile environment. Personally I rarely see the hotted up e-bikers on the road.. actually I rarely see any e-bikers on the road.. they seem to prefer to stick to bike paths. If people riding higher powered e-bikes were prepared to stay off bike paths I think I'd personally be supportive. But from what I've seen I don't think they would. I think they would rather be king of the bike path than a minnow amongst the sharks on the road. Perhaps if it was legal behaviours would be different though.

https://www.youtube.com/watch?v=sCNqodl5uQY

Oops. I think you have described me. I put my 750W motor at 40% and I do 35km/h on the flat on the bike path. I use my bell and slow down when I get near to pedestrians. Much better than mixing it with the traffic. I usually only do local roads although I did some main roads today.

[AUbicycles]

On s-pedelecs, in Germany they are legal although the rider needs a license and an approved helmet (different from regular bike helmets).

I find this fair, it is a hurdle because putting higher powered bikes in the hands of people who can’t maintain the control safety in traffic is a resl problem... so this makes them accessible... but with a fair regulation.

If you get a response from the minister... buy a lotto ticket. If you get a genuine letter (and not a canned response) buy two lotto tickets.

[skyblot]

There's been a quiet amendment to the e-bike definitions and laws...

The Federal Legislation covering the standards and definitions for e-assist bikes was amended in January. There are changes to both the 200 watt class, and 250 watt class. Common across both is the removal of throttle controls, this isn't explicitly stated but but the cycle must be pedaled to get electric assistance for the 250 watt, and must not be propelled exclusively by the motor(s) for the 200 watt.

In summary:
250 Watt: No longer required to meet euro directive EN15194. Otherwise it's simple. 250 Watt max continuous power, 25 kmh max speed with electric assist, and must be pedaling to get e-assist.

200 Watt: 200 watt total maximum of all elect motors fitted, no throttle, not e-assist speed limited, 35kg vehicle tare weight incl batteries, and must have a height adjustable seat.

I don't quite get the height adjustable seat bit.

And, this is Federal legislation and not necessarily applicable to State law. For instance, Qld legislation points to the Federal definition of the 250 watt class (previously Pedalec, now EPAC - Electrically Power Assisted Cycle) but has it's own definition for the 200 watt class (now Power Assisted Pedal Cycle).

As always, it's an individuals responsibility to be familiar with whatever rules etc apply to a chosen activity so that an informed choice can be made. The amendment can be found here: https://www.legislation.gov.au/Details/F2021L00060

[find_bruce]

Thanks skyblot

the amendment removes one of my concerns that you couldn't legally DIY because 200w motors are almost impossible to find & 250w doesn't met the euro standard unless you pay to have it tested & certified.

Throttle itself isn't illegal - you just need to add one more step & include a cadence sensor so that if the crank is not rotating the motor doesn't work

I don't quite get the height adjustable seat bit.

It's an easy way to distinguish between something designed to be powered by pedals & something designed to be powered by a motor.

Both the active pedalling requirement and the adjustable seat requirement are intended to make it easier for police to identify & prosecute some electric motor bikes, without having to test power or measure how fast they're going. If the bike is moving & the rider isn't pedaling police know it's an illegal motorbike

One look at these, with what can only be described as vestigial pedals and police know it's not any form of bicycle without going through a lengthy prosecution.

[skyblot]

On the whole, I agree too. The new 250 watt definition is much easier. Trying to certify to the EN standard would be well beyond the resources of the average person. Esp as the certification applies to the complete bike, not just the electric bit.

The throttle...I think the key point is the bike can't move under it's own power though the 250w class doesn't spell that out explicitly. With the Bafang BBS kits at present you can pedal slowly and crank the e-power up to max and the motor over runs the pedals and does all the work. Having a throttle and being able to program it to only work when pedaling is beyond the software options of all the kits I've seen so far. The Bafang BBS doesn't have that ability. We'll keep quiet about the walk assist mode!

Yes, agree with the seat height bit re the mopeds. It causes a technical problem with things like recumbents that don't have height adjustable seats. I think the reality is people will go straight to the 250watt power and just pedal. Few will be interested enough to want to use 200 watts above 25kmh, and it's a moot point in Qld for instance where the e-power has to shut off above 25kmh irrespective of whether it's a 200 or 250 watt system.

[find_bruce]

Have you seen a 200w motor for sale recently?

[Comedian]

Can anyone help me? 250w .. at what voltage?

I really struggle to understand how 250w seems to be so variable in the amount of power they put out. I have a bosch active line 250w bike. It's great... but you see people on the new "250w" bikes and they sail past up hills. It's common now to quote torque.

[warthog1]

I remember P=VI from yr12 physics a long time ago.
Power in watts = electrical potential in volts x current in amps.
So to get the same power with a higher voltage there would be less current flow

https://sciencing.com/wattage-calculated-5130879.html

Anyway I am sure there are people on here far more current than I

[skyblot]

Can anyone help me? 250w .. at what voltage?

I really struggle to understand how 250w seems to be so variable in the amount of power they put out. I have a bosch active line 250w bike. It's great... but you see people on the new "250w" bikes and they sail past up hills. It's common now to quote torque.

Voltage doesn't matter...in as much that electrical power is volts x amps. So a higher voltage system can put out 250W at fewer amps than a low voltage system, meaning you could save weight in wiring etc with higher volts. It makes a difference with high power systems, not so much at 250W.

The 250W class definition also says continuous power, nothing about peak power.

Torque is another animal. It is merely a measure of force applied. You can have high torque and zero power, eg lock your brakes then stand on the pedals and apply lots of force, but until something moves there is no mechanical power as such. (1 horsepower is 33,000 foot pounds per minute, ie move 33,000 pounds 1 foot in one minute) And of course when you let the brakes off and ride away, torque goes down (unless you can add more energy to account for the movement), and power goes up.

As to the question why two supposed 250watt bikes perform differently, I think there are too many variables to have a simple answer. What RPM is the max torque measured at, what's the torque/RPM curve like, how is the electrical power supplied and controlled in the software, what's the gearing on the bike, system weight, and ultimately how was the rider using the e-assist!

For instance, the Bafang BBS mid drives have around 70Nm torque, and a no load speed of 83 RPM (cadence) Jump on one and pedal at 90RPM and you get negligible assistance, but drop the RPM to 60 and feel the grunt. Torque sensing systems have a similar no load speed, and pedal faster than that and the assistance is zippo.

[Joeblake]

Perhaps this article might shed some light on peak power versus constant power.

https://electric-scooter.guide/guides/e ... er-motors/

I've got two e-trikes, motors nominally 250 watts, but at peak they put out a lot more (possibly 400 watts), but only for a short time, until the temperature protection cuts the motor out (particularly on a hot day climbing a long hill). Also each motor (Heinzmann) is governed to 193 rpm maximum. So the max speed depends upon the size of the wheel it is driving. My older trike Greenspeed GRT20/26 (26" rear wheel), on the flat can reach about 27 km/h, but can't climb anything steeper than about 3-4% without assistance. The second trike, Greenspeed GT16 (16" rear wheel), has the same motor but can only reach about 18 km/h on the flat but will go up a fairly steep hill (Crystal Brook Road Lesmurdie) with minimal pedal assist, at about 4-5 km/h.

Both trikes are "semi home-brew" with the motor wheels being put together by the crew at Greenspeed. I installed the throttle and electronics on the GRT20/26 myself in about 2007, while Greenspeed partially assembled the 16" wheel set up and I finished it off with a couple of SLA batteries and added solar panels on the rear to help charge them as I rode. I sent 20/26 back to the factory for refurbishment, including an under-seat battery carrier.

On the flat I can reach about 36 km/h on the 16" but the motor cuts out at around about 24 or so km/h and I have to pedal the rest.

[find_bruce]

Confusing isn't it. The same unit, watts can be used in two different ways

electrical power input: watts = volts x amps
mechanical power output: watts= torque * RPM * 2Pi/60

Mechanical power must be less than electrical power consumed but how much depends on efficiency. Where does the rest go? Heat.

The torque of a motor will always decrease as the speed of the motor increases. Because watts is based on rpm, more watts means more power, up to the maximum the motor will produce

The problem is that both are valid units & if you want your motor to sound powerful, quote electrical input. If you want to keep the power under 250w, quote mechanical output.

Then there is peak power v continuous power that Joe refers to. Higher voltage and or amperage = more power, but also more heat & temperature rises. Good motors will have temperature protection, otherwise a hotter motor will have a shorter life. Peak power is measurable, continuous power is a number that the motor manufacturer decides is an appropriate rating. They will justify it in some way, but its not consistent.

Bosch for example quotes 40Nm for the active line up to 85 Nm for the Performance Line CX, but all of these motors are rated at 250w.

I haven't got my head around the torque figures quoted, but I have a sneaking suspicion that torque is quoted because they don't want to quote peak power (which will be above 250W) and in fact the high torque motors produce a much greater peak power. The manufacturer has decided that it cannot reliably sustain that power, but that's ok because hills don't generally last that long & the 25km/h cut out will give it plenty of opportunity to provide less power & cool down.

To put it another way with a 250W motor and a 500 watt hour battery, if the input was continuously 250w, the battery would be dead flat in 2 hours & because of the speed limit, a range of less than 50 km. As you will typically get a much greater range (I would expect something more like 150km) the motor must be producing less than 250W continuously

I may be wrong & would be happy to be corrected.

[Thoglette]

Power = torque x rpm
A motor that puts out a constant 250w over its range of useful operational speed range will have torque falling off dramatically over the same range ( and notionally infinite torque at zero rpm).

Gears allow us to trade rpm for torque : that’s why we’ve got “alpine” gearing for hill climbing. Physics limits how fast you can lift any given weight with a fixed amount of power.

But this is only truely useful where your motor is producing (nearly) maximum power - either side of this power drops off. Inevitably (thanks maths) peak torque occurs at a speed lower than peak power and if gearing is fixed that’s when you accelerate fastest.


For all man made motors the designer can shape the torque (and thus power) curve by trading off various design constraints. Ie I can make a cheap 250w motor that has a very narrow torque band and will quickly overheat or one that produces 250w over a broad range of engine speeds and doesn’t overheat. But it’ll cost more.

[Joeblake]

Gears allow us to trade rpm for torque : that’s why we’ve got “alpine” gearing for hill climbing. Physics limits how fast you can lift any given weight with a fixed amount of power.

'Zackly. Which is why my two identical motors give such different "performance" - a 26" wheel is effectively a much higher gear than a 16" wheel, which therefore has more torque "low down" for climbing steeper hills, but more slowly. A wheel with 16" diameter will have a circumference of about 50" (the distance it will travel with one revolution) whereas a 26" wheel has a circumference of about 81.5"

[grt046]

I am getting a bit long in the tooth and am starting to struggle particularly on the hills when riding with my mates all of whom are 10 or more years younger.
I decided to check out the E Road bike scene and had the opportunity for a short test ride of the entry level Specialized Turbo Creo E5 over a 5.5km hilly course (65m up) Managed an average of 27 kph with 80% of the ride over 25 with no assistance. The same route with my Defy Adv resulted in a 20.5 average with similar heartbeat range on both.
Also tried a Orbea Gain M20 out in the carpark for fit and feel and have bitten the bullet and committed to one for delivery next week in time for my 80th b'day. A bit expensive but hey you can't take it with you.
Hope it works out in allowing me to continue to ride with my mates for a few years yet.