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Help choosing folding e-bike

Old 06-14-24, 01:36 AM
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Help choosing folding e-bike

I've gone through quite a few candidates for a folding electric bike, before finally settling on a choice. Now I'd like more information!

(apparently I'm unable to link to other sites until after my first ten posts - so apologies that I can't directly reference the bikes in my list)

1. I've owned a Brompton for 7 years, so naturally tried their electric bike. I didn't like the front hub drive, or the bag that sits on the front and shakes around over cobbles or uneven road-surfaces. Have also read some unreliability reports, and have a friend who's gone through three power-packs.

2. Then looked at Vello (link removed) Seemed like a really good choice until I read some very disappointing threads on this forum, and even saw the owner had been banned here for creating sock-puppet accounts. Pretty much wrote them off as untrustworthy.

3. The Ahooga Folding (link removed) looks good. Now it's discontinued in favor of the Max, and it looks like the company has lost interest in it. They don't have any retailers for this bike nearer than 600km away, but didn't want to even send a demo Folding to a new retailer in Stockholm for me (and others) to try out (only interested in sending the Max).

4. The Siggi looked like a great initiative (link removed) but the company has gone bankrupt. This one I almost invested in - literally days before I saw they were bust. Don't understand why the indiegogo is still live?

So my final choice is the Helix electric (link removed)

This bike is still vaporware - so now I need help!
Owners of the Helix bike have a Telegram channel, and maybe other inside information? Does anyone know more about the electric version? Is it coming soon? Delayed? Is the company in good shape? Are they delivering bikes?

Any information about Helix gratefully received!
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Old 06-14-24, 04:04 AM
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Not sure where you are, but how about this?

This is one you might also like.

Last edited by Schwinnsta; 06-14-24 at 04:13 AM.
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Old 06-14-24, 04:18 AM
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Seen the history of Helix, I think that the Helix Electric will be a (very) long wait because mounting a motor in the Helix frame that wasn't designed for that won't be easy (a mid-motor would cause folding issues, a rear hub motor requires some rear frame modifications).
The very small amount of bike to be sold mean that Helix will have problems to find a reliable e-assist, they will have to use some Chinese motor, battery and electronics, and like on the Brompton Electric there is high risk of reliability issues without close by manufacturer support (I understood that you are in Sweden ?).

I have also been looking for a fast folding ebike, the best solution I found is the Tern Vektron S10 based on a Bosch Performance Line mid-motor. With a Speedbox that removes the 25km/h e-assist limit and transform it into a kind of illegal speedpedelec, cruising at 45km/h requires real pedal power but is easy and average speed is much higher that with the 25km/h e-assist limit, it saves a lot of time.

But compared to a folding bike like a Brompton or Birdy, its huge and heavy.
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Old 06-14-24, 09:28 PM
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OP:
- How often will you be folding it? This speaks to needs of ease and speed of folding.
- How compact folding? Your Brompton is the king in that department, Helix a close second. Typical "bifold" frames fold much less compact and don't carry as well.
- What is the driving reason for a folding electric? Small living quarters? Stash under desk at work? Air travel? Air travel is the most stringent requirement, to meet checked bag maximum size limits, and battery issues; Bike Friday has designed their electric batteries to easily break into 3 layers, each just below max battery size limits, then reassemble easy when at destination. Other forms of travel like car trunk or train, typical bifold bikes work fine.
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Old 06-16-24, 12:27 AM
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Thanks for all the input so far.

I obviously should've clarified that my highest priorities are lightweight and a bike that's suited to day tours (that is, out-of-town partially hilly, single-day tours, where I can carry everything I need in a pack on my back, not on the bike).

The small fold is handy for taking in the car, but as bikes are very restricted or forbidden on public transport in Sweden (even folded), then I'm mostly thinking about how easy the bike can be put into the storage I have in the cellar of the house we live in - just one flight of stairs, but cumbersome with my non-folding bike.
I'm used to the speed of the Brompton fold - which I think is great, and always impresses any interested bystanders - but it's not the most important part. A few seconds each ride doesn't bother me.
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Old 06-16-24, 01:29 AM
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Originally Posted by plasticmani
Thanks for all the input so far.

I obviously should've clarified that my highest priorities are lightweight and a bike that's suited to day tours (that is, out-of-town partially hilly, single-day tours, where I can carry everything I need in a pack on my back, not on the bike).

The small fold is handy for taking in the car, but as bikes are very restricted or forbidden on public transport in Sweden (even folded), then I'm mostly thinking about how easy the bike can be put into the storage I have in the cellar of the house we live in - just one flight of stairs, but cumbersome with my non-folding bike.
I'm used to the speed of the Brompton fold - which I think is great, and always impresses any interested bystanders - but it's not the most important part. A few seconds each ride doesn't bother me.
Thank you, that helps narrow things quite a lot. Not needing an ultra-compact fold like the Brompton, opens up many more options, both lower cost, and larger wheels for better ride. A 20" wheel bifold frame (too many examples to list) is a great compromise; It should fit in a car trunk, and easier carry down to your basement, but you should verify both; It'll be about (I think) 50% longer and 50% taller in profile versus the Brompton, but that's over 2X the total bulk, so best to make sure. The advantage of 20" wheels is that you can get by with the simpler derailleur gearing (versus the internal gear hub of the Brompton, which is reliable, but more difficult to service at home, and fewer shops in the USA service IGHs, perhaps better in Europe). There are electric drives available in 20" wheels in both rear-hub-motor, and mid-drive at the crank. 20" e-bikes are usually 20"/406 wheels which have a wide selection of tires, skinny to fat. (20"/451 bikes tend to be lightweight performance models, usually skinnier tires, not as commonly available in e-bikes that I have seen, though I'm sure they're out there if you look.)

The Helix looks like a truly lovely and well-engineered bike, but have had very long waits in the past, I don't know about currently. Biggest drawback there is their choice of 24" tires, the selection is very limited.

For hills, I would normally suggest wide gearing, in english terms, minimum 21-85 gear inches, but with electric drive you should be able to get by without gears as low as the 21 gear inches.

For all electrics, I think good local support for repairs will be critical, unless you are capable yourself. So that means both a dealer that is fully qualified to diagnose things, and not just capable of replacing parts en masse, and reliable and ongoing source of parts for them. I know little on that score, others here from Europe and especially your region could tell you more, or ask your local bike seller.

Thus, the fact that you want an electric, and one with known repairability so quality, that adds a lot more to cost, so probably will not be going cheap with a low-cost bifold 20". So the Helix sounds like a good option, if available, and uses a quality e-drive, and you're satisfied with the available tire options.

I'll write more if I think of anything, but I think others here, now knowing your recent post, could add more. I know there are now some nice bikes with both electric and the Pinion transmission, as low as USD $2000, a super deal for both, but not folding.

Last edited by Duragrouch; 06-16-24 at 01:41 AM.
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Old 06-16-24, 03:31 AM
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There is no really lightweight ebike for a full day touring.

Even the Brompton Electric is not really lightweight and its battery capacity is not big enough in case of a full day touring in partially hilly area if a real e-assist is needed:
- 400Wh will be the minimum capacity needed and nowadays weight at least 2Kg with a safe UL certified packaging which is waterproof and shockproof.
- for the drive unit a hub motor weight at least 1.5kg and a mid-drive about 2kg (but there is currently no folding bike that use such a lightweight mid-drive unit)..
- this is without cabling and control panel.

So the e-assist will at least add 4kg with a weak hub drive unit, 4.5kg with a more powerful one.
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Old 06-20-24, 07:58 AM
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Originally Posted by Jipe
There is no really lightweight ebike for a full day touring.
OK - this is the problem I'm hoping the Helix solves: in my view around 12kg to 14kg is still pretty lightweight, and I've seen a few videos online of people touring across various European countries on the 'analog' Helix.

In Sweden most of the popular e-bikes are on the very heavy side: the bike I see most around town is the Rawbike which I think is around 35kg. So if I can find a ~12kg folding e-bike I'll be very happy.

PS: the Vello Bike+ Titanium is supposedly 13,5kg - I would've chosen this bike, but then I read some pretty ugly stuff on this forum, which is another reason I'm looking primarily at the Helix. But it's notable that no Helix owners are around to add any information. It really is a very niche bike apparently.

Last edited by plasticmani; 06-20-24 at 08:04 AM.
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Old 06-20-24, 08:28 AM
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If fast folding isn't a priority, Bike Friday can convert most of their bikes to an e-bike, using batteries that are small enough to be carried on planes. The conversion adds around 10# (4.5kg) to their bikes, which are typically in the 20-30# (9-13.5kg) range. They're waiting for their battery supplier though to upgrade their batteries, so I'm not sure what the delivery time is like right now.

They don't fold quickly or compactly; they're designed to feel as close of 700c bikes as possible, and they mostly succeed.
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Old 06-20-24, 09:40 AM
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How about Carbo or Gocycle?
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Old 06-20-24, 10:05 PM
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Originally Posted by plasticmani
OK - this is the problem I'm hoping the Helix solves: in my view around 12kg to 14kg is still pretty lightweight, and I've seen a few videos online of people touring across various European countries on the 'analog' Helix.

In Sweden most of the popular e-bikes are on the very heavy side: the bike I see most around town is the Rawbike which I think is around 35kg. So if I can find a ~12kg folding e-bike I'll be very happy.

PS: the Vello Bike+ Titanium is supposedly 13,5kg - I would've chosen this bike, but then I read some pretty ugly stuff on this forum, which is another reason I'm looking primarily at the Helix. But it's notable that no Helix owners are around to add any information. It really is a very niche bike apparently.
Next question: How much will you be using the electric drive?
- All the time, barely pedaling or not pedaling.
- Not much, just for some assist up hills.
- With pedaling, but constant use for higher speed and longer distance than I could pedal.

And: Maximum bike trip distance between charges?

Thanks.
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Old 06-20-24, 11:14 PM
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Sorry to say that, but these questions show a lack of experience and knowledge of the way a the current e-assist with torque sensor+cadence sensor work (Bosch, Shimano Steps, Yamaha, Panasonic, Bafang OEM...).

These e-assist are not an electric engine that the cyclist put ON or OFF depending of the ride.

They sense the torque applied by the cyclist on the pedals and add, a selected by the cyclist percentage of power (typically up to something between 300% and 400%), to the power applied by the cyclist. Its like if the cyclist had more pedaling power.

The cyclist must pedal to have an e-assist (mandatory for all ebikes in Europe, for Class 1 and Class 3 in the US), its not like the thumb throttle of an e-scooter (only US Class 2 ebikes are allowed to have a throttle activated engine).
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Old 06-20-24, 11:21 PM
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Originally Posted by Jipe
Sorry to say that, but these questions show a lack of experience and knowledge of the way a the current e-assist with torque sensor+cadence sensor work (Bosch, Shimano Steps, Yamaha, Panasonic, Bafang OEM...).

These e-assist are not an electric engine that the cyclist put ON or OFF depending of the ride.

They sense the torque applied by the cyclist on the pedals and add, a selected by the cyclist percentage of power (typically up to something between 300% and 400%), to the power applied by the cyclist. Its like if the cyclist had more pedaling power.

The cyclist must pedal to have an e-assist (mandatory for all ebikes in Europe, for Class 1 and Class 3 in the US), its not like the thumb throttle of an e-scooter (only US Class 2 ebikes are allowed to have a throttle activated engine).
I see all the time, bikes that are both pedal assist (adjustable), and purely throttled. I don't know what exists in the OP's home market, but I'm certain that if they, for example, expect to be pedaling all the time but at low effort and with high motor assist, they can express that. That's all I'm trying to determine; How far are they riding and with how much motor assist, and that info may help guestimate the size battery needed. Regarding motor power, if the bike is mid-drive so can use the gears, less motor torque needed. If a hub motor, typically larger torque is required for big hills.
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Old 06-21-24, 01:24 AM
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Just saw online, Zizzo E-Forte, I think may meet OP's criteria and not cost a fortune:

https://zizzo.bike/products/e-forte

People here have said good things about (non-electric) Zizzos.
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Old 06-21-24, 03:06 AM
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Originally Posted by Duragrouch
I see all the time, bikes that are both pedal assist (adjustable), and purely throttled. I don't know what exists in the OP's home market, but I'm certain that if they, for example, expect to be pedaling all the time but at low effort and with high motor assist, they can express that. That's all I'm trying to determine; How far are they riding and with how much motor assist, and that info may help guestimate the size battery needed. Regarding motor power, if the bike is mid-drive so can use the gears, less motor torque needed. If a hub motor, typically larger torque is required for big hills.
There are laws defining what is an ebike.

In Europe, by definition, the motor is activated by the pedaling, its not allowed to ride with a throttle activated motor, a vehicle which has a throttle activated motor is not a legal ebike.

From what I know, its the same in the US for Class 1 (20mph) and Class 3 (28mph). Class 2 (20mph) are allowed to have a throttle to activate the motor.

But there are lots of Chinese ebike sold on Aliexpress that do not comply with the EU and US law. Selling and buying such bikes is legal, but its illegal to use them on public roads.

For the torque, most mid-drive motors have an higher torque than hub motors (I mean legal one, 250W in Europe, 750W in the US).
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Old 06-21-24, 06:41 AM
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Originally Posted by Jipe
.

For the torque, most mid-drive motors have an higher torque than hub motors (I mean legal one, 250W in Europe, 750W in the US).
I think this last statement may not be valid. Mid-drives do not require as much torque since they can drive the gears directly.
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Old 06-21-24, 11:57 AM
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Bimotal

Donít know if we are allowed to post links but I just got a publicity email about a little electric motor that runs on a bikeís disc brake and is simply attached with the caliper. Looks promising!
anybody know about these? Company is called bimotal.
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Old 06-21-24, 01:23 PM
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Originally Posted by Jipe
Sorry to say that, but these questions show a lack of experience and knowledge of the way a the current e-assist with torque sensor+cadence sensor work (Bosch, Shimano Steps, Yamaha, Panasonic, Bafang OEM...).

These e-assist are not an electric engine that the cyclist put ON or OFF depending of the ride.


They sense the torque applied by the cyclist on the pedals and add, a selected by the cyclist percentage of power (typically up to something between 300% and 400%), to the power applied by the cyclist. Its like if the cyclist had more pedaling power.

The cyclist must pedal to have an e-assist (mandatory for all ebikes in Europe, for Class 1 and Class 3 in the US), its not like the thumb throttle of an e-scooter (only US Class 2 ebikes are allowed to have a throttle activated engine).
That's actually incorrect in the assumption that you're making about ALL ebikes. I own a little beater ebike that I can switch off the motor, take the battery out, and ride around with (Fiido). Then I had an ebike that REQUIRED me to pedal, or else it was like riding through oatmeal (Juiced Bikes RirRacer). I also owned the RadMission single speed ebike, which could be pedalled without power, but wasn't actually something I'd recommend. There's much higher cost electric bikes out there. and quite a few can be ridden with OR without power. Same as with cheaper mid and hub drive bikes. There are people who ONLY use the bike for hills, and throttle only ebikes available in the USA (kits and stock). Don't generalize based on your own experience.
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Old 06-21-24, 01:51 PM
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Originally Posted by Schwinnsta
I think this last statement may not be valid. Mid-drives do not require as much torque since they can drive the gears directly.
I do not say that they require more torque, I say that most have more torque.

The entry level mid-drive of the main manufacturers have now at least 50Nm, the high end 250W EU legal have 85-90Nm.

Hub motor with such value of torque have most of the time much more power than the legal EU limit.

I talk about EU legal ebike because if I understand well, the topic initiator plasticmani is in Sweden).

For TDS, you can easily pedal without power with the current Shimano Steps E6100, EP8 and EP6 mid-drive motor. Same for the TQ HPR50 mid drive.

Hub motor with an internal reduction (like the TDCM hub motor of the Brompton Electric) can also be used without power.

Its direct drive hub motor that require some power to be really usable.
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Old 06-21-24, 02:53 PM
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Originally Posted by Jipe
I do not say that they require more torque, I say that most have more torque.

The entry level mid-drive of the main manufacturers have now at least 50Nm, the high end 250W EU legal have 85-90Nm.

Hub motor with such value of torque have most of the time much more power than the legal EU limit.

I talk about EU legal ebike because if I understand well, the topic initiator plasticmani is in Sweden).

For TDS, you can easily pedal without power with the current Shimano Steps E6100, EP8 and EP6 mid-drive motor. Same for the TQ HPR50 mid drive.

Hub motor with an internal reduction (like the TDCM hub motor of the Brompton Electric) can also be used without power.


Its direct drive hub motor that require some power to be really usable.
Geared hub is easy to pedal without power, and also provides more torque. Direct drive requires power to operate efficiently and has drag (cogging) when pedaling without power. Almost all the mid drive systems can be ridden without power. The deciding factor is the weight or the ebike.

When it comes to laws, we all reside in different countries, and are governed accordingly. What's illegal in your location, as you stated, is perfectly legal across the pond. Duragrouch asked appropriate question to clarify the discussion for him. He didn't sound like he was assuming anything. The OP, if I'm correct, is located in Sweden, or somewhere else in the EU, and wouldn't be able to use a throttle. Stating location would simplify things.
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Old 06-21-24, 05:56 PM
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Originally Posted by Jipe
I do not say that they require more torque, I say that most have more torque.

The entry level mid-drive of the main manufacturers have now at least 50Nm, the high end 250W EU legal have 85-90Nm.

Hub motor with such value of torque have most of the time much more power than the legal EU limit.

I talk about EU legal ebike because if I understand well, the topic initiator plasticmani is in Sweden).
Thing is that the OP is not going to end up on a mid-drive if he is going light weight.
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Old 06-21-24, 07:32 PM
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Originally Posted by Schwinnsta
Thing is that the OP is not going to end up on a mid-drive if he is going light weight.
Possibly.

Electric motors are far better balanced than the best piston engines, due to no reciprocating mass. So they can spin fast, no problem. Motor size is often more governed by maximum torque that is required. For the same power (energy per unit time), in general, a motor with lower torque that spins faster, can be smaller than a motor that requires higher torque but spins slower. Mid-drive motors, on a bike with some reduction ratio (and this is key*), allow the motor torque to be less, and thus a smaller motor. *Note: Even with a seeming non-reduction gearing, such as 40 chainring and 30 cog, you are still getting a reduction because that is powering through a tire that is much larger than that 30 cog; A rear hub motor, however, is directly driving that rear wheel, so has much less mechanical advantage; Now, that hub motor may incorporate reduction gearing between the motor and wheel, however that is then added weight, in addition to the reduction gearing already present, if the bike has decent low gearing available in the chain system. The good news is, hub motors have plenty of space to use a large "pancake" motor which is conducive to high torque. But it will be heavier than a mid-drive motor.

Dahon has for several years offered e-bikes with both hub motors, and mid-drive; The latter, on 20" wheels, is 36 lbs, a low weight penalty for the electric upgrade, and part of this is because the mid-drive motor is on the small size, 200W. The downside of the bike is that they cleverly put the batteries in the fatter seatpost, but that still limits their size to 36V 8.7Ah. With disc brakes, it's a nice setup. But what bugs me, is that the seat tube configuration makes it impossible to mount a front derailleur, and there is no FD bracket; It IS possible to use a 2X crank on a mid-drive, if a) the motor transmits power via chain to an inner chainring, but a triple chainring is used, or b) the motor transmits power directly to the crank spindle, but it is square taper and allows mountain standard cranksets. Bike (which is a folding electric):

https://usa.dahon.com/products/unio-...42565939527869
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Old 06-21-24, 09:01 PM
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Originally Posted by Duragrouch
Possibly.

Electric motors are far better balanced than the best piston engines, due to no reciprocating mass. So they can spin fast, no problem. Motor size is often more governed by maximum torque that is required. For the same power (energy per unit time), in general, a motor with lower torque that spins faster, can be smaller than a motor that requires higher torque but spins slower. Mid-drive motors, on a bike with some reduction ratio (and this is key*), allow the motor torque to be less, and thus a smaller motor. *Note: Even with a seeming non-reduction gearing, such as 40 chainring and 30 cog, you are still getting a reduction because that is powering through a tire that is much larger than that 30 cog; A rear hub motor, however, is directly driving that rear wheel, so has much less mechanical advantage; Now, that hub motor may incorporate reduction gearing between the motor and wheel, however that is then added weight, in addition to the reduction gearing already present, if the bike has decent low gearing available in the chain system. The good news is, hub motors have plenty of space to use a large "pancake" motor which is conducive to high torque. But it will be heavier than a mid-drive motor.

Dahon has for several years offered e-bikes with both hub motors, and mid-drive; The latter, on 20" wheels, is 36 lbs, a low weight penalty for the electric upgrade, and part of this is because the mid-drive motor is on the small size, 200W. The downside of the bike is that they cleverly put the batteries in the fatter seatpost, but that still limits their size to 36V 8.7Ah. With disc brakes, it's a nice setup. But what bugs me, is that the seat tube configuration makes it impossible to mount a front derailleur, and there is no FD bracket; It IS possible to use a 2X crank on a mid-drive, if a) the motor transmits power via chain to an inner chainring, but a triple chainring is used, or b) the motor transmits power directly to the crank spindle, but it is square taper and allows mountain standard cranksets. Bike (which is a folding electric):

https://usa.dahon.com/products/unio-...42565939527869
When I made the statement I was just thinking of what is available. I would think it would be possible for there to be lightweight mid-drive folders, but I can't think of any.
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Old 06-21-24, 09:42 PM
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Originally Posted by Schwinnsta
When I made the statement I was just thinking of what is available. I would think it would be possible for there to be lightweight mid-drive folders, but I can't think of any.
Yeah there aren't as many mid-drive 20" folders, and I think one of several reasons is there is less advantage; A 26" and larger wheel, a rear hub motor needs more torque, than a 20" with hub motor. So it's easier to get by with a hub motor on 20" wheels. Nevertheless, the advantage of a mid-drive still exists on 20". The downside of a mid-drive is, while better able to climb hills at the same motor size, using the bike gearing, you are putting more wear on the bike gearing, whereas a hub motor puts ZERO wear on the bike gearing, and that is a plus. But I think mid-drives are lighter enough that it's more viable to leave the heavy battery at home for a light "manual" ride, versus with a heavier hub motor (and from what others have said about the electrical drag of an unpowered hub motor). Unless you have a non-motor rear wheel to swap in. Bromptons at 16"/349 are quite common with a swap-in front hub motor with battery on the front carrier, plus, if you get into soft soil, with pedaling, you actually have all-wheel-drive to help through. Seriously. I saw a video some months back, IIRC, a 20" with fat tires and front and rear hub motors, was shown blasting effortlessly through soft beach sand, up hills, and on the road the two motors offered varying power output.

That folding Dahon electric is not a bad setup, though range limited, and like many things Dahon, have become premium-priced for what it offers.

Last edited by Duragrouch; 06-22-24 at 02:12 AM.
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Old 06-21-24, 11:57 PM
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Originally Posted by Schwinnsta
When I made the statement I was just thinking of what is available. I would think it would be possible for there to be lightweight mid-drive folders, but I can't think of any.
You are perfectly right: its possible to be lightweight with at least 3 current compact mid-drive motor that weight 2kg or less (TQ HPR50, Fazua Ride 60 or 50 and Bosch Performance Line SX/Sprint) and a battery below 400Wh that weight 2kg or less (with the latest cell size. Batteries of all manufacturers weight more or less the same, the weight difference come from the cell assembly system and protection against water/humidity, vibrations, shock, drop test and the fact that its UL certified or not).

But indeed, as far as I know, there are no bike manufacturer that use any of those in a folding bike, they are mainly used in lightweight eMTB or eRoad bikes.

The reason could be that these 3 systems are relatively expensive, they fit for the lightweight eMTB and eRoad market since these bikes costs a lot of money, but too expensive for the folding bike market?

Indeed, the "trick" to be lightweight is to use a fast spinning, small motor with an internal reduction that bring the rotational speed to the pedaling cadence of a cyclist.
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