Cheap Brompton Conversion Kit?

shemozzle999

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Sep 28, 2009
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I believe it is the Bafang SWKU and they can run it at 48v to achieve that specification.
It was seen at the Bristol event earlier this year and blew the opposition away but was banned from the hill climb competition.
 

shemozzle999

Esteemed Pedelecer
Sep 28, 2009
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It's true, honest:p
I talked to a husband and wife couple from Devon at the BWC at Blenheim both sporting the new conversion kit on their pair of Bromptons. They went to the Bristol event and saw the said bike in action.
It convinced them to go out and make the purchase but they were only running the kit on legal 36v versions.
 

patpatbut

Esteemed Pedelecer
Apr 25, 2012
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I believe it is the Bafang SWKU and they can run it at 48v to achieve that specification.
It was seen at the Bristol event earlier this year and blew the opposition away but was banned from the hill climb competition.
Would u recommend this motor for brompton? Even with 36v, it still can run around 20mph I suppose..

Pat
 

cwah

Esteemed Pedelecer
Jun 3, 2011
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www.whatonlondon.co.uk
Best motor for brompton:


The mac 8T can do 20 mph finger in the nose and able to lift the front wheel at 2500W!
 

shemozzle999

Esteemed Pedelecer
Sep 28, 2009
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I have not personally used this motor Pat, so can not recommend it, but the couple I spoke to were very pleased with their purchase.

I biggest problem I have is sourcing one which has a suitable speed for a 16" wheel.

The Brompton wheel circumference is approximately 1.34m so to do the legal 25000 metres per hour (15.5mph) , if you divide that by 60 to convert it to minutes, that converts to 417metres per minute then divide by the 1.34 you would need a minimum motor speed of 310rpm when loaded.

The only offerings I can find are for a 26" wheel @ 201rpm.
 
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benjy_a

Esteemed Pedelecer
Jul 25, 2009
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I have not personally used this motor Pat, so can not recommend it, but the couple I spoke to were very pleased with their purchase.

I biggest problem I have is sourcing one which has a suitable speed for a 16" wheel.

The Brompton wheel circumference is approximately 1.34m so to do the legal 25000 metres per hour (15.5mph) , if you divide that by 60 to convert it to minutes, that converts to 417metres per minute then divide by the 1.34 you would need a minimum motor speed of 310rpm when loaded.

The only offerings I can find are for a 26" wheel @ 201rpm.
I can confirm that this motor is a nightmare to try and get hold of. I tried for ages but gave up and bought the Crystalyte G Series in the end because I couldn't find one.

If anybody finds a source for the 300+rpm bafang then I would buy one now and have a spare front wheel.

Ben




Sent from my GT-I9300 using Tapatalk 2
 

shemozzle999

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Sep 28, 2009
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I am awaiting delivery of a Bafang SWKB look-a-like from China that the seller says has a 340rpm speed unloaded.
I will report back if it is ok.
 
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benjy_a

Esteemed Pedelecer
Jul 25, 2009
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I am awaiting delivery of a Bafang SWKB look-a-like from China that the seller says has a 340rpm speed unloaded.
I will report back if it is ok.

Great, is this with or without sensors? Are you getting this for a Brompton?

I'll look forward to hearing how it goes. I'm also wondering if it would be possible to machine the axle flats to fit into the same (standard width) dropout that my crystalyte does so that the wheels can be interchangeable.
 

patpatbut

Esteemed Pedelecer
Apr 25, 2012
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Thanks guyz

I am looking forwards to hearing the news too. I'll probably wait for your feedback of this motor before modifying my brompton

Just wondering how the electric transport shop can get hold of this motor?

Pat
 

patpatbut

Esteemed Pedelecer
Apr 25, 2012
860
79
Best motor for brompton:


The mac 8T can do 20 mph finger in the nose and able to lift the front wheel at 2500W!
That looks awesome! but it has no gear on it then...does it hard to peddle without the battery?
 

cwah

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Jun 3, 2011
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www.whatonlondon.co.uk
Yeah, it's on the lowest gear. It's not difficult to pedal without battery but it's on the lowest gear. So it's quite hard to pedal until I reach a decent speed.

But I never pedal without battery lol, the only moment I do that is when the controller fail :p
 

shemozzle999

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Sep 28, 2009
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But I never pedal without battery lol, the only moment I do that is when the controller fail :p
I imagine you spin out at quite a low speed looking at your setup Cwah i.e. you can't turn the pedals fast enough - maybe 8mph max?
 

cwah

Esteemed Pedelecer
Jun 3, 2011
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www.whatonlondon.co.uk
I spin out from 25 mph onward. I usually use the motor to help me go up to 20-23 mph and do the remaining part myself. It looks like I'm pedaling really fast lol.

But as said, from the stop point it's quite hard to start. It's ok however because my motor has a huge torque when throwing 2000W on it.
 

shemozzle999

Esteemed Pedelecer
Sep 28, 2009
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He can supply with or without hall sensors and also has an in-wheel speed limiter sensor option utilizing the spare 9th wire in the weatherproof plug and socket he is going to retro fit for an extra $10.
This will match my existing cabling I have, so I can do a straight replacement of my existing 100mm wide motor (an YPW01, the first motor TETS of Cambridge used in their first conversion kit).
I have also bought his matching controller and led handlebar display and he is going to customize them to add a cruise control.

All my systems are 24v but he can also provide 36v.

The hub shafts have a 10mm flat and can't be reduced because the motor cable exits through the shaft unlike the crystalite.

It's early days, I doubt it will all work first time and I am sure it will need some tweaking.



btw: just got back from a lovely afternoon ride in the sun. I made a detour and visited the local community orchard, picked some apples, raided my local secret patch of cultivated blackberries and can smell the crumble cooking in the oven as I type. I will have to stop now and go a make some custard to go with the crumble. Just another advantage of being an Ebiker:eek:


Great, is this with or without sensors? Are you getting this for a Brompton?

I'll look forward to hearing how it goes. I'm also wondering if it would be possible to machine the axle flats to fit into the same (standard width) dropout that my crystalyte does so that the wheels can be interchangeable.
 

shemozzle999

Esteemed Pedelecer
Sep 28, 2009
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686
Motor supply update:

Everything seems to be going smoothly - fingers crossed.

I have just received this confirmation photo before goods were sent - goods shipped yesterday via Fedex - I expect 5/10 days delivery time:

product.jpg
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
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Cambridge, UK
Interesting so is that a spare gear assembly ?

Regards

Jerry