e-bike DIY: "Conhis" motor kits from China

daniel.weck

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Aug 8, 2009
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daniel.weck

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flecc

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That one you showed last is definitely a Bafang clone and orbitally geared Daniel. There are a couple of these alternative product manufacturers (blatant copiers), it seems part of Chinese culture that they see nothing wrong in this.

Your first link shows a switching photo in which the motors are different in the two shots. The first with the black sidewalls looks like one another member said is internally geared but very weak. The second silver wall type looks like a direct drive, but it's not possible to be certain.
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GT3

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Aug 12, 2009
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The photos and info within the website are the same as the ebay seller I bought mine off, so I would guess they are one and the same.

I don't think the motor is geared.
 

daniel.weck

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Aug 8, 2009
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The photos and info within the website are the same as the ebay seller I bought mine off, so I would guess they are one and the same.

I don't think the motor is geared.
Did you buy your motor unit from Conhis' eBay outlet ?

eBay My World - conhismotor*com

Are you happy with your purchase ?

Thanks a lot guys.
Best, Dan
 

GT3

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Aug 12, 2009
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Can't recall sellers ebay ID (no ebay from office computer!)

Very happy. I am running cheap SLA's at the mo, so very heavy, but covering hilly 16 miles in around 45 minutes, traffic dependant - I have the 1000W, not the 500.

The supplied battery connector melted immediately and I have replaced a throttle that began to malfunction, but both of those problems have been reported on here. I am not consciously using it in the wet, but have been caught out more than once and everything still works.

My view is that I'm doing this experimentally on the cheap. The conversion kit cost just over £200 delivered, so I am prepared to buy another for spares if something breaks.

350 miles and counting!
 

daniel.weck

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Aug 8, 2009
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That one you showed last is definitely a Bafang clone and orbitally geared Daniel. There are a couple of these alternative product manufacturers (blatant copiers), it seems part of Chinese culture that they see nothing wrong in this.
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Damn !! Even the description on the photo is copied from Bafang's website !!! (SWXB or smaller QSWXB model)



Suzhou Bafang Electric Motor Science-Technology Co.,Ltd.

1.brushless,used for log time(bearing),no need to maintain
2.less space and weight,great power,simple construction
3.excellent starting performance,no magnet-hysteresis damping energy consumping and good creeping slop capacity
4.no spark,no electric interference,explosion prevention
5.highh efficiency,less electric power consumption
6.large starting power,strong output fuction, stepless speed regulating
7.high cost performance,much more economical than governor
8.superior water-proof function

 
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daniel.weck

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flecc

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In that case it could be a direct drive type without internal gearing, but if so, with that small diameter it
will be totally gutless and lacking torque on voltages of 24 or 36.

Unlikely though, much more likely geared with a thin motor. The Bafang ones are still geared in the
narrower widths.
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daniel.weck

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Aug 8, 2009
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Take another look at the diagram on the large photo I posted: it is quoting 89mm for 2 obviously different widths :rolleyes: They're not really concerned with accuracy, are they :p

In that case it could be a direct drive type without internal gearing, but if so, with that small diameter it
will be totally gutless and lacking torque on voltages of 24 or 36.

Unlikely though, much more likely geared with a thin motor. The Bafang ones are still geared in the
narrower widths.
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daniel.weck

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Aug 8, 2009
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Dimensions are probably more along these lines (and these motor seem direct-drive indeed...or "gear-less" according to the descriptions)

 

daniel.weck

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daniel.weck

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"Golden Motors" seems to offer a cheap brushless+geared motor with integrated freewheel, 100mm wide (interestingly, their website shares some "similarities" with Conhis... ;) ).

hub motor,brushless motor,power wheelchair,golf trolley,wheelchair joystick controller,bike conversion kit, Lithium Iron battery,µç¶¯ÂÖÒγµ,electric bicycle




The power curve shows that it is not designed to go up to 260rpm, which would really be needed on a 16" wheel to gather decent speed (15mph).

http://www.goldenmotor.com/hubmotors/Mini Rear 36V250W Performance.pdf

http://www.goldenmotor.com/hubmotors/Mini Front 36V200W Performance.pdf

http://www.goldenmotor.com/hubmotors/hubmotor-F.pdf
 
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daniel.weck

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flecc

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As I remarked before, if direct drive those narrow and small diameter motors are unlikely to have much torque and
power. They'd be completely outclassed by the Tongxin roller drive and Bafang geared motors. Some buyers have
been disappointed with the poor performance of even the larger diameter direct drives that appear in these cheap
kits. Basically D.D. motors do need a reasonable diameter and a high enough supply voltage to have a acceptable
performance that compares with the popular geared hubs like the Bafang type.

You only have to look at what e-bike manufacturers fit to see the position. They avoid the cheap direct drive
types and almost universally use the more expensive internally geared hub motors. Direct drive motors can be ok,
the BionX being a reasonable size one that is used by the odd manufacturer, but it's a very expensive and
sophisticated setup.
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daniel.weck

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Aug 8, 2009
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The Golden Motor "Mini" kit is actually a geared motor. There's lots of info on their forum, such as:

"The 36V 250W mini geared hub produces 20.03Nm of torque @172.9rpm (23km/h or 14.3mph with 28" wheel).
To produce this torque it will draw 13.53Amps and consume 487Watts to output 362.5Watts @ 74% efficiency.

The 36V 500W non-geared hub produces 18.24Nm of torque @266.1rpm (35.5km/h or 22mph with 28" wheel).
To produce this torque it will draw 18.43Amps and consume 659.7Watts to output 508.1Watts @ 77% efficiency.

The geared motor will produce 8.68% more torque and use 26.2% less energy, but speed will be 35% slower.

At 362.5Watts output, the geared motor is working well above its 250W rating.
"

As I remarked before, if direct drive those narrow and small diameter motors are unlikely to have much torque and
power. They'd be completely outclassed by the Tongxin roller drive and Bafang geared motors. Some buyers have
been disappointed with the poor performance of even the larger diameter direct drives that appear in these cheap
kits. Basically D.D. motors do need a reasonable diameter and a high enough supply voltage to have a acceptable
performance that compares with the popular geared hubs like the Bafang type.

You only have to look at what e-bike manufacturers fit to see the position. They avoid the cheap direct drive
types and almost universally use the more expensive internally geared hub motors. Direct drive motors can be ok,
the BionX being a reasonable size one that is used by the odd manufacturer, but it's a very expensive and
sophisticated setup.
.
 

daniel.weck

Esteemed Pedelecer
Aug 8, 2009
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No gears.

Dimensions are probably more along these lines (and these motor seem direct-drive indeed...or "gear-less" according to the descriptions)
I've just received a reply from "Lynn" (or Shyou Shang) from the Conhis firm. O(∩_∩)O~

I asked for technical data, and they "kindly" send me a 1600x1200 photo of the motor's internals (see attached image) :D :rolleyes:

So far then, "Nine Continents" and "Golden Motors" are the only known (i.e. english-accessible) Chinese alternatives/copies to Suzhou Bafang's (8-Fun) brushless/geared mini motor unit.



shyoushang@126.com
E-mail1: conhismotor.lynn@gmail.com
E-mail2: lynn@conhismotor.com
SKYPE : conhismotorlynn@hotmail.com
MSN : conhismotorlynn@hotmail.com
WEB : Conhis Motor- Motor manufacturer - Buy Motor from ConhisMotor
 

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flecc

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Oct 25, 2006
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And Goldenmotors are normally direct drive ones anyway (poor quality too). They probably buy in the geared ones.
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daniel.weck

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Aug 8, 2009
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And Goldenmotors are normally direct drive ones anyway (poor quality too). They probably buy in the geared ones.
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Well, there are rumours on Endless Sphere and the Golden Motor's own forums that they are outsourcing the manufacturing of internal elliptical geared units (probably old stock from Suzhou Bafang, actually), but some official representative has been denying this... :rolleyes:

Anyway, GM seem to have problems with their controllers, they are now trying to push sales of their new "Magic Pie" controller, which is quite exiting technically but equally flawed...apparently. :eek:

I think I'll stick to either Bafang or Tongxin... :D
 

daniel.weck

Esteemed Pedelecer
Aug 8, 2009
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Yep, they have gears:



Well, there are rumours on Endless Sphere and the Golden Motor's own forums that they are outsourcing the manufacturing of internal elliptical geared units (probably old stock from Suzhou Bafang, actually), but some official representative has been denying this... :rolleyes:
 

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