Hello, and my first conversion, any advice please.

Brian_S

Finding my (electric) wheels
Jul 2, 2024
5
1
Hello good folks,

After some intensive research on an e-bike conversion I though it would make sense to join a good forum.
Originally from the Midlands, now based in Cheshire, and work in the electronics industry.

Looking to convert my old Cube XMS120, 26 inch wheeled mountain bike, as its been sitting there for a while and I'm not good at selling things, plus I like to tinker. Additionally, I dont think I'd be happy with 250W.
My other half is about to purchase an Ampere as it the best we could find for someone just shy of 5ft tall. So I need to get a move on.

The brief is I'd like an all rounder with a good range, nothing serious in any particular category.

I've done a lot of browsing re hub moto versus direct drive and feel like I'm going round in circles now, So I'm 99% committed to getting a Bafang 750W with a 20Ah 48V battery, just need to get the template and check the 20Ah will fit as it looks quite tight. I've done most of the other measurements and it seems possible for my Cube XMS.

On the basis that I do this, I'd be very grateful if I can get some help here to get me started:
  1. Are all the 750W Bafangs programmable and is the software easily available, the supplier I am considering is showing an updated version with a better curve. Im not sure how many variants there are of this 750W motor
  2. I am thinking Hailong max 48V, 20Ah, is this a good choice
  3. Any recommendations for supplier for these kits, or individual components, the supplier I am considering has 100% feedback and gave me a very fast reply and good information. Electric Bikes Home - https://www.ebay.co.uk/itm/394892367306
  4. I'm thinking of getting the 500C display
  5. Anything else important to consider around the above kit choice that Ive not mentioned
I'm quite frustrated with Amazon and eBay because its difficult to find the cheapest supplier for the same kit of components because of all the variables. I'm guessing buying as a kit is the best route. Is there a defacto small list of suppliers that people here go to?

Open to other possibilities should anyone think this is not a decent option

Thanks for reading

Sincerely,

Brian
 

RollingChunder

Pedelecer
Dec 7, 2023
96
36
Chances are you'd prefer a hub motor as it's a more relaxed riding and owning experience. Unless you enjoy changing gears and climbing challenging, 'off-the-seat' terrain with all the maintenance that comes with that. Pswpower and topbikekit are decent chinese sellers rather than a random on ebay. Make sure you get a battery with name branded cells.
 
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thelarkbox

Esteemed Pedelecer
Aug 23, 2023
1,215
376
oxon
Hi Brian and welcome on in It sounds like you have read the same 'articles' as i did about a year ago when i took the ebike plunge too. Mid drives gotta be the best option .. er... perhaps not..

As for a bafang 750w mid drive, really?? I would strongly urge you to remain within the regs and if a high power mid drive is what you need.. talk to Mr woosh who sells the 750w tdz mid drive with a legit manufacturers 250w label and eu/uk classification. Granted only something like 260 dodgy ebikes were confiscated in a recent year by the UK plod, but that could change very quickly depending on public whim.


But if your partner is ridding a legit ebike your not gonna be tootling along 10mph faster very often are you??

In the end i ended up buying a basic hub kit from yose-power for circa £400 inclusive of everything inc the tools to fit. and it has ample power to shift 90+kg of me and my heavy shopping loads.. 24 tins of diet coke for £6.50 at tesco atm ;) a couple of those and the regular shop are no problem..

Cheshire can be hilly so perhaps a mid drive is a good fit for you, that is where they shine (that and speeding hehe) as they take advantage of a bikes gearing .

Perhaps give us a clue to where and what sort of terrain you intend to ride on, and what sort of distance you want to cover on a single battery charge.. Then some of the real ebike experts could pitch in with more targeted suggestions..

Whichever way you go -- welcome to the 'dark side' ;) And enjoy the Wheeee factor on your new bike..
 
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saneagle

Esteemed Pedelecer
Oct 10, 2010
6,842
3,169
Telford
In case you don't know, the 750w version is illegal to use in UK. The motor must be marked 250w.
 

Laser Man

Pedelecer
Jul 1, 2018
200
127
Michelmersh SO51
Most kits will allow much higher power than the nominal 250W for short periods.
For instance my MXUS rear hub kit from Woosh - 36V, 18A controller - maxes out at around 650 to 740W depending on the battery charge.
So there's plenty of power for acceleration and getting up hills without resorting to illegal motors.
 

Brian_S

Finding my (electric) wheels
Jul 2, 2024
5
1
Chances are you'd prefer a hub motor as it's a more relaxed riding and owning experience. Unless you enjoy changing gears and climbing challenging, 'off-the-seat' terrain with all the maintenance that comes with that. Pswpower and topbikekit are decent chinese sellers rather than a random on ebay. Make sure you get a battery with name branded cells.
The chap in the store that is selling the Ampere recommended getting a hub motor rather than direct drive, all his own bikes use hub motors and said they give very little hassle. I will look at the suppliers you recommend. I dont think I'm going to do anything too extreme, just trying to cover all bases. Very grateful for your help
 
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Brian_S

Finding my (electric) wheels
Jul 2, 2024
5
1
Hi Brian and welcome on in It sounds like you have read the same 'articles' as i did about a year ago when i took the ebike plunge too. Mid drives gotta be the best option .. er... perhaps not..

As for a bafang 750w mid drive, really?? I would strongly urge you to remain within the regs and if a high power mid drive is what you need.. talk to Mr woosh who sells the 750w tdz mid drive with a legit manufacturers 250w label and eu/uk classification. Granted only something like 260 dodgy ebikes were confiscated in a recent year by the UK plod, but that could change very quickly depending on public whim.


But if your partner is ridding a legit ebike your not gonna be tootling along 10mph faster very often are you??

In the end i ended up buying a basic hub kit from yose-power for circa £400 inclusive of everything inc the tools to fit. and it has ample power to shift 90+kg of me and my heavy shopping loads.. 24 tins of diet coke for £6.50 at tesco atm ;) a couple of those and the regular shop are no problem..

Cheshire can be hilly so perhaps a mid drive is a good fit for you, that is where they shine (that and speeding hehe) as they take advantage of a bikes gearing .

Perhaps give us a clue to where and what sort of terrain you intend to ride on, and what sort of distance you want to cover on a single battery charge.. Then some of the real ebike experts could pitch in with more targeted suggestions..

Whichever way you go -- welcome to the 'dark side' ;) And enjoy the Wheeee factor on your new bike..
Thank you for the warm welcome.
Your point is valid regarding the legal power limit. I'll need to look into the 750W with the 250W label, is this some sort of loophole? I noticed some Bafang suppliers were offering 250W stickers but guessed it is illegal.
Regarding the terrain, I just want to do a bit of everything road, grass, up some hills in the local parks, a bit of off road, nothing too serious though. I just dont want to be caught short trying to do something and not being able to. We are quite busy with other things so I doubt we would go out often but when we do it would be for a full day, her bike is 250W, 14Ah, with 65nM of torque which appears impressive for 250W.

Looks like I'm back to the drawing board for now. ps. Your use case example is very useful and I appreciate the tip for the 24 diet coke from Tesco :)
 

Brian_S

Finding my (electric) wheels
Jul 2, 2024
5
1
Most kits will allow much higher power than the nominal 250W for short periods.
For instance my MXUS rear hub kit from Woosh - 36V, 18A controller - maxes out at around 650 to 740W depending on the battery charge.
So there's plenty of power for acceleration and getting up hills without resorting to illegal motors.
Thanks for this information, it sounds like a possible option for me. I took a look on their website but did not see the MXUS brand, but I have read good things about MXUS in the past.
I've emailed them to see what they recommend.
Cheers
 

saneagle

Esteemed Pedelecer
Oct 10, 2010
6,842
3,169
Telford
Thank you for the warm welcome.
Your point is valid regarding the legal power limit. I'll need to look into the 750W with the 250W label, is this some sort of loophole? I noticed some Bafang suppliers were offering 250W stickers but guessed it is illegal.
Regarding the terrain, I just want to do a bit of everything road, grass, up some hills in the local parks, a bit of off road, nothing too serious though. I just dont want to be caught short trying to do something and not being able to. We are quite busy with other things so I doubt we would go out often but when we do it would be for a full day, her bike is 250W, 14Ah, with 65nM of torque which appears impressive for 250W.

Looks like I'm back to the drawing board for now. ps. Your use case example is very useful and I appreciate the tip for the 24 diet coke from Tesco :)
The power from the motor is not a loophole. It's allowed under the law. The law says that the motor must be rated at 250w. There is no law about how much power can be put through it. There are some 250w motors that can easily handle 3000w, and I know of one used on a pedicab that can easily do 3500w. In simple terms, the motor must be marked or listed as 250w, and you can use as much power as the motor can handle.
 

thelarkbox

Esteemed Pedelecer
Aug 23, 2023
1,215
376
oxon
I am not an expert in any regard to this matter, however while the 250w legal limit is a thing, but is also meaningless.. You can do your own in depth homework if necessary ;)

But the basic schoolboy physics is Volts X Amps = Watts.

So an ebike with a controller capable of delivering 15a peak power the usual for an off the shelf hub kit/bike and a 36v battery Fully charged to 42v Could Push out upto 15x42 630w if pushing you uphill. Yes there are real world losses in efficiency and friction and heat etc .. but 630 is quite a bit more than 250.....
And yes as the battery voltage drops so will the peak performance.. but that happens anyway, thats how batteries work..

And what if you apply a 48vbattery/controller (52?54?v fully charged)...

And add an after market controller upgrade to 17a, 20a ... is possible as long as your battery can supply that draw too.
All legal as the only criteria is the rating of the motor..

As for the legality of the Woosh TDZ motor it is according to all sources in here all above board, since TDZ manufacture the motor they legitimately can label it.. but thats my lay and casual understanding.. There are a number of threads on the subject of this motor from Woosh in here which is where i got my info ;)

but its common to find motors rated 250w in the uk/eu rated 500w or 750w elswhere in the world
 
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Saracen

Esteemed Pedelecer
Aug 24, 2023
532
61
Chances are you'd prefer a hub motor as it's a more relaxed riding and owning experience. Unless you enjoy changing gears and climbing challenging, 'off-the-seat' terrain with all the maintenance that comes with that. Pswpower and topbikekit are decent chinese sellers rather than a random on ebay. Make sure you get a battery with name branded cells.
Can you ride a broken hub drive / flat battery hub drive like a normal bike, you can MID drive if the motor dies or your battery does ?
 

Laser Man

Pedelecer
Jul 1, 2018
200
127
Michelmersh SO51
Can you ride a broken hub drive / flat battery hub drive like a normal bike, you can MID drive if the motor dies or your battery does ?
Yes - absolutely.

And - if you want - you can turn off the assist and ride it like a normal bike that way.
 
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esuark

Esteemed Pedelecer
Jul 23, 2019
272
198
kent
Can you ride a MID drive if the chain breaks you can a hub drive? just evening things up!
 

Ghost1951

Esteemed Pedelecer
Jun 2, 2024
1,590
627
Can you ride a MID drive if the chain breaks you can a hub drive? just evening things up!
Yes - you probably can, as long as you have a small, cheap chain tool in your kit, and a quick link.

I never ride my bike further than I am prepared to push it home, unless I have tyre mending kit and a pump and other essential tools like those above.
 

esuark

Esteemed Pedelecer
Jul 23, 2019
272
198
kent
Yes - you probably can, as long as you have a small, cheap chain tool in your kit, and a quick link.

I never ride my bike further than I am prepared to push it home, unless I have tyre mending kit and a pump and other essential tools like those above.
.....and if you haven't. I`ll add I'm as you I have all that gear with me.
 
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Benjahmin

Esteemed Pedelecer
Nov 10, 2014
2,592
1,747
70
West Wales
I think you are a bit confused on motor types. Direct drive motor are hub motors but they have no gearbox or clutch. This means that they are always rotating even when free wheeling. This leads to a lot of rolling resistance. They are good at high speed on the flat but not good at hill climbing. At low speeds they are inefficient and turn a lot of your precious battery power into useless heat.
Direct drive motors are power hungry, especially in stop start riding. They are known to be very heavy on batteries.

A geared hub motor's rotor spins at higher rpm making it more efficient at the lower speeds. Also it has a clutch which will disengage during freewheeling leading to less rolling resitance.
Bear in mind that your battery needs to have a maximum current delivery that is at least 10% more than the maximum current of your controller, in order to not damage the battery.
A '250w'rated hub motor is more than capable of taking 17A @36v - this is 612w or 816w @48v and still legal. Get a '750w' rated motor and it is illegal no matter what you do with it.
 
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saneagle

Esteemed Pedelecer
Oct 10, 2010
6,842
3,169
Telford
I am not an expert in any regard to this matter, however while the 250w legal limit is a thing, but is also meaningless.. You can do your own in depth homework if necessary ;)

But the basic schoolboy physics is Volts X Amps = Watts.

So an ebike with a controller capable of delivering 15a peak power the usual for an off the shelf hub kit/bike and a 36v battery Fully charged to 42v Could Push out upto 15x42 630w if pushing you uphill. Yes there are real world losses in efficiency and friction and heat etc .. but 630 is quite a bit more than 250.....
And yes as the battery voltage drops so will the peak performance.. but that happens anyway, thats how batteries work..

And what if you apply a 48vbattery/controller (52?54?v fully charged)...

And add an after market controller upgrade to 17a, 20a ... is possible as long as your battery can supply that draw too.
All legal as the only criteria is the rating of the motor..

As for the legality of the Woosh TDZ motor it is according to all sources in here all above board, since TDZ manufacture the motor they legitimately can label it.. but thats my lay and casual understanding.. There are a number of threads on the subject of this motor from Woosh in here which is where i got my info ;)

but its common to find motors rated 250w in the uk/eu rated 500w or 750w elswhere in the world
One small correction: 15A at 42v can't push out 630w. Instead, it sucks in 630w. Overall efficiency is around 70%, so it will push out around 440w maximum. If the motor speed drops to less than 50% of its max rpm, it would be closer to 380w, but will drop off rapidly if the motor goes slower than that.
 

thelarkbox

Esteemed Pedelecer
Aug 23, 2023
1,215
376
oxon
One small correction: 15A at 42v can't push out 630w. Instead, it sucks in 630w. Overall efficiency is around 70%, so it will push out around 440w maximum. If the motor speed drops to less than 50% of its max rpm, it would be closer to 380w, but will drop off rapidly if the motor goes slower than that.
Always happy to stand corrected, lets nip this misinformation in the bud..
 
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