First ladies ebike recommendations

[Lilliput]

I'm brand new to the world of ebikes and slightly overwhelmed by the choice! I'd love some recommendations, either for specific bikes or for general things I should be looking for.

Budget is around £2K.

I'm 5'3 and slight, looking for a step through, upright bike which could take a child seat on the back rack.

Battery-wise I don't need a huge range as it'll mostly be used for pottering around town. Terrain is fairly flat but I'm not a strong cyclist so when there is a hill I need some help! But I don't know what that translates to in terms of power/torque.

Thanks in advance

 

[MelbournePark]

Ok its daytime here in Melbourne, and winter is coming. Its wet and for us, pretty cool at 12.7 degrees Centigrade (that's only 34 degrees fahrenheit) and its raining. So a great time here to get a good bike buy . Our financial year finishes at the end of June, plus high interest rates and tax increase are souring, so bike dealers are doing it tough.

you were given a bad cadence sensored hub bike to test.
A modern controller reduces its power to keep you pedalling at all times if you slow down your pedalling when you go round a corner for example.
That is an important point to keep in mind. If your test bike does not do this, ask for another one.
Controllers respond more quickly to a torque sensor than a cadence sensor because cadence sensor requires more intensive computing but the difference in response time is not very big, we are talking about may be a few tenths of a second here. You soon won't take much notice. The advantage of cadence sensor over torque sensor is that cadence sensor lets you ride up a hill with much more ease.

Once again, that depends on the bike's settings. The full input on the three centre drives bikes I tested, didn't need much pedal effort in their high power settings. And that is logical programming. Lightening the pedal effort to no apparent input, they did let the power stop. So there is a difference. But since I come from a push bike, the centre drive felt much smoother and more natural. And on the steep hill test, there was no need to hit the bottom of the hill with speed ... my test was to enter the hill (it not being very long) and then move up the hill.

 

[MelbournePark]

Bonzo, thanks for the statistics. Thanks for the info on the dominance of hub motors in China, and around the world.
Just a few points. You said the following:

" However on a mid-drive motor with lets say 85Nm it may be you get 90Nm for its lowest gear but its very slow with a high cadence and then as you go higher you get 70Nm, 50Nm, 40Nm, 30Nm, 20Nm, 10Nm etc so the faster you go the less assistance you get. "

That's not true. I would refer you to Newton's second and third laws. The first law is that force = mass times acceleration. And his third law says that for every action (force) there is an equal and opposite reaction.

Gears don't extinguish that force.

The hub motor does have more of its energy available, because there are less friction losses. But a gear box is able to utilise its energy better in varying loads. And its energy losses are slight. In low power elect motors, the gears - for my usage - are well worth the very slight energy loss due to friction.

The basic issue is that a hub motor is stuck inside a single gear. Namely the wheel. If you put a hub motor from a 28" wheel into a 20" wheel, its performance is going to behave very differently. That's because of the design of the motor and primarily because the wheel is the single gear the electric force is restricted to.

There is no magic loss of energy due to gears, there's a tiny bit lost, and there 's typically a little more mass in a mid drive setup, in my case in the bikes I have just now ordered, one kilogram more compared to the same bike with a rear hub drive setup. The idea you are propagating, is that gears can loose in your example, 90% of their energy. They don't.

I'm not unfamiliar with electric motors, energy, and gearboxes. I ran a factory with 45 large electric motors, and most of them drove gearboxes, and many had variable speeds. I've burnt out and re-wound a lot of electric motors. Recycling plastics from rubbish film into virgin equivalent film, around 48 tonnes of film produced a week, all from recycled rubbish, into about 1000 Olympic football stadiums of heavy thick plastic film every year.

The big issue IMO for bikes, is that most of them are artificially restricted. We would not be having this discussion, if there were no power limits on bikes. I reckon if there weren't such limits, the logical solution would be a hub drive. Afterall Dr Porsche used that concept in the first world war, to power Germany's rail system, so that less or even no locos were required. Ironically now, Porsche is one of the few electric car makers that actually incorporates a gear box. You can research why elsewhere!

For myself, I've done enough testing now, and I am opting for a mid drive solution. This is because I want a folding bike first, secondly light bike that is fun to ride, is compact when folded, well priced, and can handle my riding requirements. One is easy access to my yacht, via road and then a pier and then marina dock, which has some tight turns. also to ride it around my area on bike tracks an now then cross roads. Maybe go to the supermarket instead of driving or (rarely) walking. A major want is to be able to handle non mown grass, and also to be able to attempt to get from a river bank up the typical steep inclines that we often encounter when we go camping in the Australian bush. My wife also has ridden a fair bit, and she did not like the instant response feel of the hub drives - those obviously were not optimal setup ones for us "newby" ebike riders..

I could list advantages and disadvantages for both types. I don't want to do that though. I have also checked the spare parts issues going into the future, and I am assured I won't have issues getting parts, the issues will be the extent of the delay. But if I do wear things out, that will be good - because I we will have used the bikes.

 

[Bonzo Banana]

Bonzo, thanks for the statistics. Thanks for the info on the dominance of hub motors in China, and around the world.
Just a few points. You said the following:

" However on a mid-drive motor with lets say 85Nm it may be you get 90Nm for its lowest gear but its very slow with a high cadence and then as you go higher you get 70Nm, 50Nm, 40Nm, 30Nm, 20Nm, 10Nm etc so the faster you go the less assistance you get. "

That's not true. I would refer you to Newton's second and third laws. The first law is that force = mass times acceleration. And his third law says that for every action (force) there is an equal and opposite reaction.

Gears don't extinguish that force.

The hub motor does have more of its energy available, because there are less friction losses. But a gear box is able to utilise its energy better in varying loads. And its energy losses are slight. In low power elect motors, the gears - for my usage - are well worth the slight energy loss due to friction.

The basic issue is that a hub motor is stuck inside a single gear. Namely the wheel. If you put a hub motor from a 28" wheel into a 20" wheel, its performance is going to behave very differently. That's because of the design of the motor and primarily because the wheel is the single gear the electric force is restricted to.

There is no magic loss of energy due to gears, except for a tiny bit in friction, and also, there is typically more mass in a mid drive setup. The idea you are propagating, is that gears can loose in your example, 90% of their energy. They don't.

I'm not unfamiliar with electric motors, energy, and gearboxes. I ran a factory with 45 large electric motors, and most of them drove gearboxes, and many had variable speeds. I've burnt out and re-wind a lot of electric motors. Recycling plastics from film into film, about 1000 Olympic football stadiums of heavy plastic film every year.

The big issue IMO for bikes, is that most of them are artificially restricted. We would not be having this discussion, if there were no power limits on bikes. I reckon if there weren't such limits, the logical solution would be a hub drive. Afterall Dr Porsche used that concept in the first world war, to power Germany's rail system, so that less or even no locos were required. Ironically now, Porsche is one of the few electric car makers that actually incorporates a gear box. You can research why elsewhere!

For myself, I've done enough testing now, and I am opting for a central gearbox solution. This is because I want a light bike that is easy to ride, and is compact, well priced, rides well, is fun, and can handle both my pier and marina access (I have a yacht and ride an old bike to the marina and it has some tight turns) and I also want my bike to be able to handle non mown grass and be able to attempt to get from a river bank up the typical steep inclines that I reckon are common when we go camping in the Australian bush. My wife also has ridden a fair bit, and she did not like the instant reponse feel of the hub drives - the obviously not well setup ones for us "newby" ebike riders.

I think you have misunderstood a lot there. A mid drive motor uses a very high rpm low torque motor through internal gears to generate a high torque at low speed. You can create more torque with the gearing and this is still true of the external gears in a bicycle drivetrain. The torque doesn't remain the same. If one gear is 1:1 so the torque at the crank is 90Nm and therefore the torque at the rear wheel is 90Nm minus losses in the chain then you have to understand when the front crank is 90Nm and the gearing is high and the rear wheel rotates 3x as much for one crank rotation 3:1 then that power is now 30Nm minus the losses through the chain. This is very simple and undisputable data which is completely accepted everywhere. If you have a cassette that is 11-52T that is getting close to 5x so you roughly get a fifth of the torque in the highest gear compared to the lowest.

The whole point of gears is to amplify our torque for hills at the expense of speed. You must understand that you need to go to a low gear on your bike to tackle steep hills?

 

[cyclebuddy]

...in a mid drive setup, in my case in the bikes I have just now ordered, one kilogram more compared to the same bike with a rear hub drive setup.

I'm intrigued. What e-bikes have you ordered?

 

[MelbournePark]

I'm intrigued. What e-bikes have you ordered?

Today I payed a deposit, for two Dahon K-One bikes. The shop is putting racks, are carry bag, mud guards on them, and changing the tyres from 1.75 wide tyres to Schwable 2.15 Fat somethings. I wanted more aired tyres, for ride and also to handle grass better. The rear motor version was 1 kg lighter at 19kg. Otherwise the bikes were similar. The cost of each bike without the options was in British Pounds after tax, 1,115. The rear wheel hub motor version would have cost $1,000 pounds. I don't know if the bike is sold in the UK. Its available in the USA, and its on special in the USA at the moment. There's a lighter bike available now with a different motor gearbox, and a nicer frame, the whole combo is only 17kg for the mid motor bike. The motor used in that bike is only 200 watts. I don't think there is a hub motor available in that bike. I presume one will come out later. My wife and I both loved the bike.

 

[MelbournePark]

The whole point of gears is to amplify our torque for hills at the expense of speed. You must understand that you need to go to a low gear on your bike to tackle steep hills?

Some mid motor bikes don't have gears at all. They can still go up hills. If the gearing is similar, they'd go up marginally worse (due to weight and friction effects - Newton's second law - than a single geared hub motor bike.

As far as bikes with gears, I guess you don't understand Newton's third law. Shame.

 

[MelbournePark]

And I sort of wrote this:


Newton's second law of motion states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. Mathematically, it can be expressed as F = m * a, where F represents the net force applied to the object, m is its mass, and a is the resulting acceleration.

When it comes to mid motor bicycles, where the motor is positioned near the bike's bottom bracket (center motor), Newton's second law is applicable. The motor in a mid motor bicycle provides additional force or power to assist the rider's pedaling. As a result, the net force acting on the bicycle is increased, leading to enhanced acceleration. This is particularly advantageous when climbing hills or riding on challenging terrains since the combined power of the rider and the motor helps overcome resistance.

In contrast, a front hub motor bicycle, where the motor is integrated into the front wheel hub, doesn't directly impact Newton's second law. The motor in this configuration provides assistance by driving the front wheel, but it doesn't affect the net force applied to the entire bicycle. Instead, the force generated by the motor is transmitted through the wheel to propel the bike forward. The rider's pedaling, in combination with the motor's power, helps achieve the desired acceleration.

Newton's third law of motion states that for every action, there is an equal and opposite reaction. This law is relevant to both mid motor and front hub motor bicycles. When the motor applies a force to propel the bike forward, an equal and opposite reaction force is exerted on the motor itself. In a mid motor bicycle, this reaction force is primarily absorbed by the bike's frame and structure, which are designed to handle the additional stress. In a front hub motor bicycle, the reaction force is transmitted through the fork and other components connecting the front wheel to the frame.

Overall, while both mid motor and front hub motor bicycles involve the application of Newton's second and third laws, the specific mechanical configurations and positioning of the motor affect how these laws come into play. The mid motor design has the advantage of utilizing the bike's gears and achieving a balanced weight distribution, which can result in improved acceleration and climbing ability.

Well, actually, its the first time I've used ChatGTP. That took ... a couple of seconds. Interestingly, maybe its not all that smart, as it forgot to mention tyres!

 

[cyclebuddy]

Today I payed a deposit, for two Dahon K-One bikes. The shop is putting racks, are carry bag, mud guards on them, and changing the tyres from 1.75 wide tyres to Schwable 2.15 Fat somethings. I wanted more aired tyres, for ride and also to handle grass better. The rear motor version was 1 kg lighter at 19kg. Otherwise the bikes were similar. The cost of each bike without the options was in British Pounds after tax, 1,115. The rear wheel hub motor version would have cost $1,000 pounds. I don't know if the bike is sold in the UK. Its available in the USA, and its on special in the USA at the moment. There's a lighter bike available now with a different motor gearbox, and a nicer frame, the whole combo is only 17kg for the mid motor bike. The motor used in that bike is only 200 watts. I don't think there is a hub motor available in that bike. I presume one will come out later. My wife and I both loved the bike.

It's not clear (Dahon don't say) which of Bafang's extensive mid-drive motors is actually fitted, or if it's CanBus or UART... the later most desirable if you want to be able to tweak the bikes performance.

One of my own e-bikes uses a Bafang Mid-motor; being UART, you can really rinse the thing to optimise its performance (in standard form, they tend to be programmed to be a bit mediocre/lacklustre). If you intend to get the most from your K-One(s), you won't be getting far on a small 8.7Ah seat-post battery so you may want to consider buying a spare or two (I doubt you'll be getting anything like the claimed 30 miles unless it's in de-tuned form).

 

[Bonzo Banana]

Some mid motor bikes don't have gears at all. They can still go up hills. If the gearing is similar, they'd go up marginally worse (due to weight and friction effects - Newton's second law - than a single geared hub motor bike.

As far as bikes with gears, I guess you don't understand Newton's third law. Shame.

It's not that I don't understand Newton's third law I honestly don't understand why you are quoting it here its not applicable surely to how gearing works and the whole point of gearing to increase torque at the expense of speed or vice versa.

I think I've seen mid-drive motors used in single speed ebikes very occasionally but for me that is pointless as you are losing one of the benefits to scale power through the gears. I just don't see the point of it at all. It can still provide powerful torque though if that single gear is a low gear but if its normal single speed gear ratio then you are limiting the power of the mid-drive motor and causing excessive drivetrain wear. Surely then a hub motor would be far, far superior for that application.

 

[lenny]

Well, actually, its the first time I've used ChatGTP.

Leave out the ChatGPT son.

 

[StuartsProjects]

Well, actually, its the first time I've used ChatGTP.

So be honest.

Did you write the post yourself, or was it the output from an unverified text engine like ChatGTP ?

 

[Woosh]

And I sort of wrote this:


Newton's second law of motion states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. Mathematically, it can be expressed as F = m * a, where F represents the net force applied to the object, m is its mass, and a is the resulting acceleration.

When it comes to mid motor bicycles, where the motor is positioned near the bike's bottom bracket (center motor), Newton's second law is applicable. The motor in a mid motor bicycle provides additional force or power to assist the rider's pedaling. As a result, the net force acting on the bicycle is increased, leading to enhanced acceleration. This is particularly advantageous when climbing hills or riding on challenging terrains since the combined power of the rider and the motor helps overcome resistance.

In contrast, a front hub motor bicycle, where the motor is integrated into the front wheel hub, doesn't directly impact Newton's second law. The motor in this configuration provides assistance by driving the front wheel, but it doesn't affect the net force applied to the entire bicycle. Instead, the force generated by the motor is transmitted through the wheel to propel the bike forward. The rider's pedaling, in combination with the motor's power, helps achieve the desired acceleration.

Newton's third law of motion states that for every action, there is an equal and opposite reaction. This law is relevant to both mid motor and front hub motor bicycles. When the motor applies a force to propel the bike forward, an equal and opposite reaction force is exerted on the motor itself. In a mid motor bicycle, this reaction force is primarily absorbed by the bike's frame and structure, which are designed to handle the additional stress. In a front hub motor bicycle, the reaction force is transmitted through the fork and other components connecting the front wheel to the frame.

Overall, while both mid motor and front hub motor bicycles involve the application of Newton's second and third laws, the specific mechanical configurations and positioning of the motor affect how these laws come into play. The mid motor design has the advantage of utilizing the bike's gears and achieving a balanced weight distribution, which can result in improved acceleration and climbing ability.

Well, actually, its the first time I've used ChatGTP. That took ... a couple of seconds. Interestingly, maybe its not all that smart, as it forgot to mention tyres!

ChatGPT still has some training to go through before it understands properly Newton's laws.

 

[MelbournePark]

I didn't know about chat GTP until last night!!! Yep - its database is shallow ... I tested it with automobiles and it was wrong!

Bonzo - Newton's laws do apply. You said that the energy ie torque - decreases due to the gears, and you listed the decrease in torque from 80 to 70 to 60 down to 10, when one changes the gears.

Newton's law shows that a force is met by an opposite reaction ie the force is not lost. You debated that it is lost due to the gears. Then later, you tried to talk about speed issues.

The facts are that the loss from a mid motor is minimal. There is extra lost power from the mid motor when one looses a tiny bit of power from the friction of the gears.

If one really considers the issues, a mid motor will accelerate better than hub motor by using gears. And if the gears benefit the power usage - such as on heavy grass which slows the bike down, or thick sand, or up hills - then the mid motor's ability to use gears increases efficiency. That means a mid motor is more efficient, if the gears are a benefit to the bike.

In cars, trains etc, electric motors do not use gears. The reason is due to the excess of torque in an electric engine that will achieve an auto speed of double the speed limit. Despite Porsche using a second gear.

I reckon if bikes had excess power, then the benefit of a mid motor would be somewhat marginal, excluding the handling improvement.

Its early days though with the electronic controls, and perhaps, with authorities deciding what is legal and what is not. In Australia's largest populated State (Province/Region etc) of New South Wales, the have recently (in March/April of this year ) doubled the permitted wattage for an bicycle aided by an electric motor, it now being a 500 watt motor where 250 watts was the previous maximum allowed (for street use). So NSW now has double what the rest of our Country allows.

If one ignores the loss of energy from having a heavier wheel rotating around (the mass of which also looses energy) a well controlled hub motor is excellent. IMO it has one very huge advantage - it can regenerate power by being the brake.

For me though, I much preferred the mid motor for our particular usage.

 

[MelbournePark]

It's not clear (Dahon don't say) which of Bafang's extensive mid-drive motors is actually fitted, or if it's CanBus or UART... the later most desirable if you want to be able to tweak the bikes performance.

I doubt I will. I did research them some time ago though, and established which one it was. But that maybe 7 weeks ago. On the control setup - the hub motor version had a large display, while the mid motor version had a small and mean looking display. Although the small display was easy to use, it was small screen but with big buttons. Both of the e-bikes (hub and mid) have an area for I presume electronic controls. The performance was fantastic actually, and besides increasing the top speed, I didn't feel a need to fiddle with the controls. I had thought that changing to 48 volts would not assist warranty and doubted it would be easy to do on those bikes, and also, would decrease the small battery range. The bikes felt very sprightly though, even on setting one the bike felt quick, and two quite powerful.

The specification is supposed to be a Bafang M400, and when I looked I thought it might be that, a 420, a 420, or even, something completely different. IMO the specs changer according to country. I will report back though. As long as its the same setup as what we tested, I'll be happy.

I can report later when I find out their bad points.

I am curious though about how the top speed is calculated? Because if its from the gears rather than the tyres/wheels, a change in the front sprocket would increase the speed. Both bikes have a very low first gear compared to what our bikes have.

I won't need much range. But the batteries are super expensive. While the NCM bikes have a price of only 225 pounds for their 560 32v 15.5 AH battery, the price for a replacement for the K-one battery which is more than one third smaller, is 316 pounds.

I face this type of issue in my yacht, which is an ocean going racing boat that is setup for single or duel handed sailing. The issue with short handed sailing is that instead of steering the boat yourself, you rely on an electronic autopilot, with wind sensors, an gyro compass, a computer all digesting the inputs and then operating an electrically powered set of rudders. The power usage is a bit over 8 amps of 12 volt power. That comes down to for a bike battery (dividing by 2.6 although that figure is debatable) the continuous consumption in bike battery terms is 3.2 amp hours. That might not sound much but over 30 hours, that comes to close to 100 amp hours. So for that NCM bike, I'd need to have 6 of their batteries. Which would cost of course, 1,350 pounds. And actually, that is a lot less than the lithium I was wanting to install, or the AGM Lifeline 6 volt batteries that I did install. So IMO, those NCM batteries were a great price. Although I don't know much about what cells they use. There is a huge variance in cell quality out there.

I wanted to replace all my "house" batteries with lithium - lithium iron phosphate - batteries, which are non combustable as unlike bike lithium batteries, a lithium iron phosphate battery doesn't produce oxygen when it is radically overheated (which won't happen until around 500 C). So no problem I thought ... but I could not insure the boat, and even if I accepted partial insurance, no electronic installer would install such batteries, due to their own insurance issues preventing them from such installations. Of course all insurers insisted on having lithium batteries installed by approved marine electrical companies. Catch-22.

Sorry for all that - but the electronic guys all said - it is not relevant. What actually matters at sea, is re-charging used batteries. Because no matter how much capacity one has, when its run out, one then has to get the power back in. I could go on at length about various other complications! The beauty of lithium, is that they accept charge at a linear rate. So there is no slowing down of accepting charge, like lead acid batteries do, as their resistance increases, they accept less charge, so they have to endure a prolonged absorption charge. Lithium just accepts all its charge at a fast rate, and at 99.x% it then resists a touch more. And at 90% or 70% charge, lithium does not damage its cells, unlike lead acid which sulphates and starts to destroy itself unless fully charged.

For my main bike usage, the same issue applies. It's about getting the power back into the batteries.

So for me with a caravan, I will have to use its solar power (or a petrol generator) to get the power back in. So a large battery is no real help, except at the beginning. I was looking hard actually for 3 amp chargers. But when I did the math on two chargers for each bike, I thought the bottleneck would be on my inverters (which convert the caravan's battery power to 240 volt) which can run the bikes' chargers.

So for me, efficiency of the bike is important. But we also lowered efficiency with the fatter tyres (for the dirt and grass) plus the guards and rack.

We also tested the bikes with the power turned off, and the bikes didn't seem to have extra resistance when riding. Our current folding bikes weigh 17.5 kg. So the difference is only 3.3 kg with the battery flat. The bikes standard are 2.5 kg heavier, but we added plastic guards, fatter tyres and a rear rack. A hub motor also has a bit of extra resistance with the battery turned off, although in my tests I did not feel that resistance, although theoretically it is there. Free wheeling on a mid motor is supposed to be similar to a normal bike, and logically that is the case excluding their extra weight.

The other issue for us is getting exercise. We want to push the pedals, and get that exercise. Which is probably why we were sensitive to the feel of the bike, which had a very smooth integration of power to human effort => fun factor.

The worst thing about the bikes is that they are not step through. We'd have liked that, but at least they are similar to our current bikes in the horizontal bar support.

 

[Woosh]

I didn't know about chat GTP until last night!!!

it's ChatGPT, Generative Pre-trained Transformer. it's not GTP.
It's such a fascinating and topical subject since its launch - 30 Nov 2022, now clocking up more than 100 million users.
Surely it must have been extensively reported in Australia too?

The facts are that the loss from a mid motor is minimal. There is extra lost power from the mid motor when one looses a tiny bit of power from the friction of the gears.

If one really considers the issues, a mid motor will accelerate better than hub motor by using gears. And if the gears benefit the power usage - such as on heavy grass which slows the bike down, or thick sand, or up hills - then the mid motor's ability to use gears increases efficiency. That means a mid motor is more efficient, if the gears are a benefit to the bike.

There are a lot of problems in your understanding of mid and hub motors, torque, force and power. There are quite a few aspects to consider that you should really discard the pre-conceived idea that mid motors are more efficient than hub motors. Both systems have equally strong proponents.
Let's discard first those direct drives, they suffer from magnetic cogging (aka magnetic locking between rotor and stator) so not suitable for riding without power and are generally not road legal here and also in Australia.
In general, the reduction gearbox and clutch system inside a hub motor is smaller, lighter and more efficient than the same in a middle motor. Just ride the bike without power, although the difference isn't big, you can still feel it. The loss though the transmission is slightly more with a crank drive. Hub drives are lighter and more efficient in this respect. If your crank motor clutch or gearbox fails, sometimes you can't even ride the bike.
Next, crank motors transmit power through the chain, so increase wear. Hub motors lessen the effort on hills thus reduce wear.
Lastly, crank motors require you to be on the right gear all the time so frequent gear shifting is a must. Mistakes with the gears cause no peroblem with hub drives but can be expensive with crank drives.

 

[AntonyC]

There are a lot of problems in your understanding of mid and hub motors, torque, force and power.

And for the sake of completeness

Its wet and for us, pretty cool at 12.7 degrees Centigrade (that's only 34 degrees fahrenheit) and its raining.

 

[MelbournePark]

Yep, there's advantages and disadvantages in both systems.

Wear issues on bikes have always been around. That's why you check your gear. Punctures are the unpredictable issues for me though.

We all have different priorities. For me, I wanted a natural fun ride. And because I also want to use the bike in the Australian bush, being able to change a tube and tyre without issues in the outback matters to me. I'm also very comfortable with what resembles a normal bike, if one ignores a bit of bulk around the pedals. I can even fit my old Dahon bike's wheels and tyres. I might even put them on my roof rack, behind a spare 4WD tyre that lives on the roof.

I don't regard the different ways of going about aiding a rider as some sort of competition, or being right or wrong, and I am certainly not worried about having chosen the wrong technology. I had a simple choice between two similar bikes, similar brands, with one with a hub motor, and the other a mid motor. Both myself and my wife loved the mid motor feel, so that's what we are getting.

 

[lenny]

I didn't know about chat GTP until last night!!!

I look forward to ignoring ChatGPT's review, son.

 

[MelbournePark]

I look forward to ignoring ChatGPT's review, son.

Yes, its scary stuff. My son told me about it. He is in building automation. He said its scary. He used it to make a draft for a building process - and it was very close to what he wanted. In about 10 seconds.

I tested with diesel V6 motors, and it got things quite wrong, and was shallow on information, referring me to the makers! It said for instance, that BMW had put V6 diesel engines into X3, X5, 5 and 7 series, etc. But in fact, BMW have never sold a V6 diesel. On speaking to my son, he said there was a professional version too. And that there was a bunch of similar Ai software, and huge investment in it.

Henry Kissinger at almost 100 years!!!! Said a few days ago in a long interview with the Economist, that the world threat to the world (outside of Russia and China v the USA), was the difficulty and perhaps eventual impossibility of turning Ai off. He reckoned 5 years humanity could be in trouble. While it sounds like a bad movie, there is a lot of investment into Ai.

Please excuse me being off topic.

And thanks for the advise and information guys, it was most helpful.

 

[MelbournePark]

It's not clear (Dahon don't say) which of Bafang's extensive mid-drive motors is actually fitted, or if it's CanBus or UART... the later most desirable if you want to be able to tweak the bikes performance.

One of my own e-bikes uses a Bafang Mid-motor; being UART, you can really rinse the thing to optimise its performance (in standard form, they tend to be programmed to be a bit mediocre/lacklustre). If you intend to get the most from your K-One(s), you won't be getting far on a small 8.7Ah seat-post battery so you may want to consider buying a spare or two (I doubt you'll be getting anything like the claimed 30 miles unless it's in de-tuned form).

The bikes I am getting don't have the Bafang mid motor. The rear motor is a Tongsheng TSDZ2 @ 32 volts. The newer Dahon A-20 which isn't available in Australia yet, also is reputed to have a Tongsheng, but likely a different version, as its 200 Watts. Its said to perform well. I doubt I would be able to hack it as I think much of the electronics are welded into the frame, sort of in a box just behind the bottom of the seat post area.