5 ms·

808Wh battery and 100 miles of range. These two numbers track with each other and are roughly believable. OTOH, with a battery this big, a generator powered by

808Wh battery and 100 miles of range. These two numbers track with each other and are roughly believable. OTOH, with a battery this big, a generator powered by the pedals, and regen braking this thing has to be heavy. I'd expect it to weigh at least 80 lbs. More likely 100. The fact that their "specs" say nothing about weight suggests they're embarrassed about the weight.

jeffbee 1y ago
Regen braking is how you can tell this was designed by a moron. The energy balance simply does not favor regenerative braking on a bicycle, especially a bicycle that flippantly ignores aerodynamics like this one does. A bicyclist loses roughly all of their energy to air resistance. It's not a truck. There is not substantial potential energy to be recaptured going down hills.
- big_toast 1y ago
  Not a big cyclist but is that still true for lower speed city riding (typical to flat european cycling prone countries), hillier SF, or mountain biking? It seems obviously true to typical racing or distance scenarios. And i notice the wind even at lower speeds on e-bikes in SF. But between their quad scenario and what I imagine as the urban car replacement scenario it doesn't seem as obvious.
  - jeffbee 1y ago
    Yes, it is true at all speed and under all conditions. The system simply does not have the mass that would give it a great deal of gravitational potential energy, and it reaches a power equilibrium with the air at low speeds. Example: 100kg rider at 15 kph = .24W-h kinetic energy. At this speed there is probably roughly 11N of air and rolling resistance, so the steady state power is about 3W-h per km. If you go 1km between stops, or more, the amount you can expect to gain by regeneration is extremely small. It could perhaps extend your range by 5%, generously.
    - emil-lp 1y ago
      Let's say 130kg (80kg driver + 50kg bike) going 30km/h (e-bike limit) is ~1.25Wh.
    - big_toast 1y ago
      Does that assume no pedaling though? In my experience the pain of starts and stops dominates the joy of steady state pedaling. Presumably the 3Wh/km is free/"exercise" or some portion. Whereas the .24Wh (re-gainable w/ some loss) is all sweat and pain imo. If I'm understanding the math, maybe that scales the regenerative range extension % by your tolerance for pedaling?
      - adgjlsfhk1 1y ago
        The difference is that humans (unlike motors) have pretty low max power limits.
        big_toast 1y ago
        I assume this comment in relation to the starting from a stop being unpleasant? If it's w.r.t. effect of low max power on low cumulative generation, I agree it does seem like a little silly to arbitrage your power generation this way. But maybe the tradeoff is worth it in some circumstances in their view? Or maybe it's just a low cost addition as other commenters say.
- edaemon 1y ago
  What do you mean? The regenerative braking only kicks in when you engage the brake lever. It's not going to add much range but it's free, I don't see any downside to including regenerative braking.
  - jeffbee 1y ago
    It isn't free. How could it be free? It requires at least an electronic control system and a pressure sensor.
    - LoganDark 1y ago
      It was already going to have some sensor for, say, the brake light.
    - 01HNNWZ0MV43FF 1y ago
      Are there popular e-bikes without electronic motor control?
    - edaemon 1y ago
      It's the same control system that operates the motor. The motor is just being used as a generator. I'm not sure which pressure sensor you mean, like in the brake lever? E-bikes with hydraulic brakes already have sensors for power cutoff (and in this case for brake lights).
    - numpad0 1y ago
      3-phase motors are controlled by torque commands into the driver. Give it a value and it generates requisite voltages to fill the gap between current state and desired state. Give it a positive value and the driver spins up the motor, give it a negative and it artificially spins down the motor progressively by commanded amounts. So especially off-throttle regen is completely free. IIUC.
    - cyberax 1y ago
      If you engineer it properly, it doesn't add _any_ weight or complexity. All you need is a bit different arrangement of power transistors and some software. Why existing bikes don't use it? Because you need software or a more complicated controller, and the amount of regenerated energy is indeed not that large.
- CorrectHorseBat 1y ago
  My e-bike has regen braking and it's definitely noticable, but I don't know how much it helps
- mvkel 1y ago
  Boosted Boards have regen, and in typical use, it extends range by about 10%. It was an incredibly intuitive system; instead of brakes, you regen your way to a stop. I don't see how this would be any different. Or, it's certainly not "moronic"
  - jeffbee 1y ago
    The Boosted board imbued the word "moronic" with layers of meaning that it previously lacked. In particular its regenerative brake, with its penchant for sudden disengagement, literally killed riders.
- Spunkie 1y ago
  I find regen exciting for it's ability to slow down my brake pads getting shredded every month. The fact that I get some energy back from it is mostly a bonus.
  - nradov 1y ago
    How are you shredding brake pads every month?
    - Spunkie 1y ago
      My town is on the side of a volcano, a 30% grade is like the average hill here. That combines with the heavy weight of an ebike, another 50lb+ of cargo in the saddlebags, plus my exceptionally fat ass means I burn through a pair of front brake pads about once a month if I'm running errands most days.
      - skeeter2020 1y ago
        >> a 30% grade is like the average hill here. So the steepest roads in the world have small sections where the grade exceeds 30%; none maintain it or "average" 30%.
        nradov 1y ago
        Seriously. Even the Mauna Kea volcano climb doesn't have 30% grades. https://www.strava.com/segments/1504789 https://www.strava.com/segments/1504789
        Spunkie 1y ago
        Ya sorry I always get it mixed up with the % grade thing. When I'm in my car the dash reads on the hills here between 12° all the way up to 16° on the switchback into the valley. The new market is up a 14° hill. So closer to ~24% grade average maybe? It's damn steep is the point regardless.
      - jeffbee 1y ago
        Do you sell many trombones?
- Izikiel43 1y ago
  > The energy balance simply does not favor regenerative braking on a bicycle Here in Seattle with all the hills it might
  - skeeter2020 1y ago
    it has nothing to do with the hills; it's the mass and the power output of the system. Bicycles are light and humans (even with electric pedal assist) are weak.
- doctoboggan 1y ago
  Think of regen braking as a way to save an expendable part (brake pads). Instead of dumping your kinetic energy into heating up some brake pads, you can dump your kinetic energy back into the battery. That it happens to recharge (likely only a few small percent) is just a bonus.
- gnarcoregrizz 1y ago
  agreed. regen does nothing on my e-moto. i'll drop 5000 feet in elevation and the battery percentage doesn't go up.
dylan604 1y ago
My eBike is close to 90lbs, but it is a large cargo bike touted as a "small car replacement". It is close to a tandem bike in size with a steel frame. I'm so used to it now, but I live in a house and never need to carry it up stairs. It does mean that I need an expensive bike rack to support that weight.
- newsclues 1y ago
  I lived in an apartment with only stairs where I owned a light gravel bike roughly 20 lbs and an old mtb that was about 35, and my back really felt the difference between the two. 100 lbs would be unmanageable.
  - dylan604 1y ago
    With a bike the size of mine, I don't think I would own it if I was living in an apartment. It's just too big even without considering stairs. It's long. It's wide. It's perfect for how I'm using it not in an apartment. Not every bike is a fit for every rider. The point I really fell like I left out is that with that size and weight of the bike plus being able to haul 300lbs, the motor and battery combo is rated for 45 miles. Not once have I felt like I needed longer range. It's not that kind of bike. I use it for tooling around while shopping or leisure rides topping out at 35 miles. Even at 35 mile rides, by battery still has plenty remaining as I still heavily rely on my meat motor.
- aidenn0 1y ago
  I have a 75lb cargo ebike and I'm afraid to mount it on my stand to work on it.
CorrectHorseBat 1y ago
My Stromer ST3 weights about 30kg, has an 1kWh battery but doesn't come anywhere close to even 100km range at full speed. I suspect pedal-by-wire will only be slightly heavier since it doesn't need gears, but the range will probably be even worse.
CyberDildonics 1y ago
800 wh and 100 miles? There is no way anyone gets that. 800 watt hours for $4,500 is absurd too.
FpUser 1y ago
>"808Wh battery and 100 miles of range. These two numbers track with each other and are roughly believable." Absolutely not. Unless you have baby in a saddle and going 10mph
hamdingers 1y ago
Rivian figures they can take the 149,000Wh they would've put into a $100,000 truck, split it into 186 ebikes and take home $837,000.
buenzlikoder 1y ago
It's difficult to say these numbers are believable or not as they depend on speed and pedal input, but given my own experience and reading some tests/forum, they are off by 2x to 3x.

jeffbee 1y ago

Regen braking is how you can tell this was designed by a moron. The energy balance simply does not favor regenerative braking on a bicycle, especially a bicycle that flippantly ignores aerodynamics like this one does. A bicyclist loses roughly all of their energy to air resistance. It's not a truck. There is not substantial potential energy to be recaptured going down hills.

big_toast 1y ago
Not a big cyclist but is that still true for lower speed city riding (typical to flat european cycling prone countries), hillier SF, or mountain biking? It seems obviously true to typical racing or distance scenarios. And i notice the wind even at lower speeds on e-bikes in SF. But between their quad scenario and what I imagine as the urban car replacement scenario it doesn't seem as obvious.
- jeffbee 1y ago
  Yes, it is true at all speed and under all conditions. The system simply does not have the mass that would give it a great deal of gravitational potential energy, and it reaches a power equilibrium with the air at low speeds. Example: 100kg rider at 15 kph = .24W-h kinetic energy. At this speed there is probably roughly 11N of air and rolling resistance, so the steady state power is about 3W-h per km. If you go 1km between stops, or more, the amount you can expect to gain by regeneration is extremely small. It could perhaps extend your range by 5%, generously.
  - emil-lp 1y ago
    Let's say 130kg (80kg driver + 50kg bike) going 30km/h (e-bike limit) is ~1.25Wh.
  - big_toast 1y ago
    Does that assume no pedaling though? In my experience the pain of starts and stops dominates the joy of steady state pedaling. Presumably the 3Wh/km is free/"exercise" or some portion. Whereas the .24Wh (re-gainable w/ some loss) is all sweat and pain imo. If I'm understanding the math, maybe that scales the regenerative range extension % by your tolerance for pedaling?
    - adgjlsfhk1 1y ago
      The difference is that humans (unlike motors) have pretty low max power limits.
      - big_toast 1y ago
        I assume this comment in relation to the starting from a stop being unpleasant? If it's w.r.t. effect of low max power on low cumulative generation, I agree it does seem like a little silly to arbitrage your power generation this way. But maybe the tradeoff is worth it in some circumstances in their view? Or maybe it's just a low cost addition as other commenters say.
edaemon 1y ago
What do you mean? The regenerative braking only kicks in when you engage the brake lever. It's not going to add much range but it's free, I don't see any downside to including regenerative braking.
- jeffbee 1y ago
  It isn't free. How could it be free? It requires at least an electronic control system and a pressure sensor.
  - LoganDark 1y ago
    It was already going to have some sensor for, say, the brake light.
  - 01HNNWZ0MV43FF 1y ago
    Are there popular e-bikes without electronic motor control?
  - edaemon 1y ago
    It's the same control system that operates the motor. The motor is just being used as a generator. I'm not sure which pressure sensor you mean, like in the brake lever? E-bikes with hydraulic brakes already have sensors for power cutoff (and in this case for brake lights).
  - numpad0 1y ago
    3-phase motors are controlled by torque commands into the driver. Give it a value and it generates requisite voltages to fill the gap between current state and desired state. Give it a positive value and the driver spins up the motor, give it a negative and it artificially spins down the motor progressively by commanded amounts. So especially off-throttle regen is completely free. IIUC.
  - cyberax 1y ago
    If you engineer it properly, it doesn't add _any_ weight or complexity. All you need is a bit different arrangement of power transistors and some software. Why existing bikes don't use it? Because you need software or a more complicated controller, and the amount of regenerated energy is indeed not that large.
CorrectHorseBat 1y ago
My e-bike has regen braking and it's definitely noticable, but I don't know how much it helps
mvkel 1y ago
Boosted Boards have regen, and in typical use, it extends range by about 10%. It was an incredibly intuitive system; instead of brakes, you regen your way to a stop. I don't see how this would be any different. Or, it's certainly not "moronic"
- jeffbee 1y ago
  The Boosted board imbued the word "moronic" with layers of meaning that it previously lacked. In particular its regenerative brake, with its penchant for sudden disengagement, literally killed riders.
Spunkie 1y ago
I find regen exciting for it's ability to slow down my brake pads getting shredded every month. The fact that I get some energy back from it is mostly a bonus.
- nradov 1y ago
  How are you shredding brake pads every month?
  - Spunkie 1y ago
    My town is on the side of a volcano, a 30% grade is like the average hill here. That combines with the heavy weight of an ebike, another 50lb+ of cargo in the saddlebags, plus my exceptionally fat ass means I burn through a pair of front brake pads about once a month if I'm running errands most days.
    - skeeter2020 1y ago
      >> a 30% grade is like the average hill here. So the steepest roads in the world have small sections where the grade exceeds 30%; none maintain it or "average" 30%.
      - nradov 1y ago
        Seriously. Even the Mauna Kea volcano climb doesn't have 30% grades. https://www.strava.com/segments/1504789 https://www.strava.com/segments/1504789
      - Spunkie 1y ago
        Ya sorry I always get it mixed up with the % grade thing. When I'm in my car the dash reads on the hills here between 12° all the way up to 16° on the switchback into the valley. The new market is up a 14° hill. So closer to ~24% grade average maybe? It's damn steep is the point regardless.
    - jeffbee 1y ago
      Do you sell many trombones?
Izikiel43 1y ago
> The energy balance simply does not favor regenerative braking on a bicycle Here in Seattle with all the hills it might
- skeeter2020 1y ago
  it has nothing to do with the hills; it's the mass and the power output of the system. Bicycles are light and humans (even with electric pedal assist) are weak.
doctoboggan 1y ago
Think of regen braking as a way to save an expendable part (brake pads). Instead of dumping your kinetic energy into heating up some brake pads, you can dump your kinetic energy back into the battery. That it happens to recharge (likely only a few small percent) is just a bonus.
gnarcoregrizz 1y ago
agreed. regen does nothing on my e-moto. i'll drop 5000 feet in elevation and the battery percentage doesn't go up.

dylan604 1y ago

My eBike is close to 90lbs, but it is a large cargo bike touted as a "small car replacement". It is close to a tandem bike in size with a steel frame. I'm so used to it now, but I live in a house and never need to carry it up stairs. It does mean that I need an expensive bike rack to support that weight.

newsclues 1y ago
I lived in an apartment with only stairs where I owned a light gravel bike roughly 20 lbs and an old mtb that was about 35, and my back really felt the difference between the two. 100 lbs would be unmanageable.
- dylan604 1y ago
  With a bike the size of mine, I don't think I would own it if I was living in an apartment. It's just too big even without considering stairs. It's long. It's wide. It's perfect for how I'm using it not in an apartment. Not every bike is a fit for every rider. The point I really fell like I left out is that with that size and weight of the bike plus being able to haul 300lbs, the motor and battery combo is rated for 45 miles. Not once have I felt like I needed longer range. It's not that kind of bike. I use it for tooling around while shopping or leisure rides topping out at 35 miles. Even at 35 mile rides, by battery still has plenty remaining as I still heavily rely on my meat motor.
aidenn0 1y ago
I have a 75lb cargo ebike and I'm afraid to mount it on my stand to work on it.

CorrectHorseBat 1y ago

My Stromer ST3 weights about 30kg, has an 1kWh battery but doesn't come anywhere close to even 100km range at full speed. I suspect pedal-by-wire will only be slightly heavier since it doesn't need gears, but the range will probably be even worse.

CyberDildonics 1y ago

800 wh and 100 miles? There is no way anyone gets that. 800 watt hours for $4,500 is absurd too.

FpUser 1y ago

>"808Wh battery and 100 miles of range. These two numbers track with each other and are roughly believable." Absolutely not. Unless you have baby in a saddle and going 10mph

hamdingers 1y ago

Rivian figures they can take the 149,000Wh they would've put into a $100,000 truck, split it into 186 ebikes and take home $837,000.

buenzlikoder 1y ago

It's difficult to say these numbers are believable or not as they depend on speed and pedal input, but given my own experience and reading some tests/forum, they are off by 2x to 3x.