Anybody have more info on these new GM MINI hub motors?

[Russell]

Here is a picture of a mini motor kit from their website. I don't know if it's geared or direct. It looks like it's sensorless.



The motors are also available for purchase alone.

http://goldenmotor.com/

So who will be the first adventurous soul to try one out and report back?

-R

 

[voicecoils]

87% sure it is a bafang pmgr. Sold by various and tends to strip internal nylon gears when used over 200-350w rated voltage.

Lots on the forum search "bafang"I

 

[Russell]

87% sure it is a bafang pmgr. Sold by various and tends to strip internal nylon gears when used over 200-350w rated voltage.

Lots on the forum search "bafang"I

I currently own a Bafang so I do know about them and these do look like a Bafang however the drawings on the GM website do not match the size of the Bafang. I suppose they could have repackaged them. I did email GM and this is the response I got to my questions;


Hello,


Could you tell me more about the new MINI HUB MOTORS you have for sale on your website?

Are the motors GEARED on (sp) DIRECT drive?

Do the motors use HALL SENSORS or are they SENSORLESS?

How many SPEED freewheel cluster will the rear mini hub motor accept (6,7,8)?

Does either the front or rear mini hub motor accept DISC brakes?

Are ALL rim sizes BLACK?


Thank you,

Russ xxxxxxxxx




Hi Russ,

It is geared on direct drive.

The motor uses hall sensors, but it can work with hall sensorless controller.

It can take 6-speed freewheel cluster.

Both front and rear motor can take disc brake if the front fork wide enough.

It is black but we can change it to other colour if order is in volume.

Thanks,

signature


I meant to ask "Are the motors GEARED or DIRECT drive?" Given the size I suppose they have to be geared however he also states it can work "sensorless". I know the Nano motor is sensorless but I've never seen the Bafang operated that way. The picture I posted above seems to show just 3 phase power wires which of course would mean they are running it sensorless but it could mean like the Nine Continent motor kit offered by ebikes.ca that it HAS hall sensors but they choose to run it sensorless.




-R

 

[marks]

$205usd for a stealth like kit is awesome...

 

[voicecoils]

The bafang can be operated sensorless. Knuckles on this forum has done so. I have a sensorless board from him which connects to the controller but haven't used it myself yet.

It's possible it might not be a bafang. There's actually lots of variants from 8fun:

http://www.szbaf.com/en/Product.asp?CategoryID=279

The case design does look identical in every way. Golden sells the motor only quite inexpensively if someone wants to try it.

 

[Russell]

Here are the drawings for the front and rear GM mini motors;

http://goldenmotor.com/hubmotors/hubmotor-F_WHEEL.pdf

http://goldenmotor.com/hubmotors/hubmotor-R_WHEEL.pdf

The REAR motor does look like a Bafang. I thought at first the 143.50mm measurement they were giving was the spoke hole to spoke hole distance however upon magnification it appears to be the outside diameter which then matches the Bafang.

The size of the FRONT motor is stated as 161mm which is different from any Bafang I've seen. The front motor in the kit picture above however doesn't look that large.

The Bafang website is kind of a mess to navigate but this is from their catalog;

http://www.szbaf.com/images/5-6.jpg

If you magnify the specs you can see the outer dimension of a couple of the motors are 143.50mm.

So yes it does look like these are Suzhou/Bafang/8FUN motors. I sent another email asking that question so we'll see if they answer.

I am debating whether to motorize my Kona Smoke 2-9 and the leading candidate is the Ezee front kit with the Bafang in second, the Nine Continent in third and the WE kit in fourth. I do like the idea of sensorless so if the GM mini kit is indeed sensorless then I might go for it though I should probably wait until I see how my current Bafang performs (darn winter). The 700C kit is the most expensive but with $120 shipping it still comes in at just $346. Not bad.

-R

 

[docnjoj]

Hey Voicecoils! Did you ever get your Bafang operating with the steel gear(s)? I am healed enuff to attempt to reassemble my trike and give it a try! The motor is ready! Any suggestions for success? that Golden motor sure looks like my Bafang and the diameter is the same!
otherDoc

 

[John in CR]

I think these may be the motors I'm about to start testing, and the ones I have are definitely not Bafangs. I'll measure one against the drawing measurements. The ones I have are definitely beefier than the Bafangs, with a larger planetary gears with fewer teeth. Plus the gear itself is about 50% thicker than the Bafang, so it should hold up better. These are supposedly 500W motors at 48V, and good for 32kph in a 26" wheel at 48V. Unfortunately I have no other technical data, and don't know the manufacturer. My plan is to beat one up at 60V and see if I can make it fail hauling my 240lbs up hills.

John

 

[Russell]

John,

I'm curious to see how the motors you have measure up to the GM FRONT mini motor, that's the one that is bigger than a normal Bafang.

http://goldenmotor.com/hubmotors/hubmotor-F_WHEEL.pdf

It would be nice to get a beefed-up Bafang (or whatever it is) available at a lower price than the BMC/EZEE geared motors.

-R

 

[voicecoils]

I think these may be the motors I'm about to start testing, and the ones I have are definitely not Bafangs. I'll measure one against the drawing measurements. The ones I have are definitely beefier than the Bafangs, with a larger planetary gears with fewer teeth. Plus the gear itself is about 50% thicker than the Bafang, so it should hold up better. These are supposedly 500W motors at 48V, and good for 32kph in a 26" wheel at 48V. Unfortunately I have no other technical data, and don't know the manufacturer. My plan is to beat one up at 60V and see if I can make it fail hauling my 240lbs up hills.

John

Interesting. The rear Bafang disc and non disc version use a planetary gear with MORE teeth. Not sure exactly how many but a similar diameter but finer pitch. The motor on the rear unit I saw is also much more sealed then mine (which has exposed windings on both sides).

 

[John in CR]

I got my caliper out and mine aren't either of those GM's.

Voicecoils,

I bring up the planetary gears to the problem with the Bafangs using controllers more powerful than the motors. I have the larger rear Bafang, but burned it up with a bad wiring combo + frustration cranking the throttle before I ever got to test the gears. It's my understanding that since the gears are straight, not helical, that only one tooth at a time bears the load. With the new motors I have, the larger profile teeth and the wider thickness of the gear would seem to combine to ensure a stronger gear. Also, the flat portion of the Bafang gears is dead flat, like they are cut from a nylon tube and a bearing is pressed in the center. These other gears aren't flat like that on the sides. It's some kind of taper. I know it's subjective, but even before seeing the greater thickness, these look stronger and more precision made. I asked my Chinese connection and he says they are special, and didn't balk at me over-volting them, but that could just be hype, especially since he's the same guy insisting that the kit does regen even though the geared motor freewheels.

Unfortunately thanks to a 1" vs 1.125", head tube vs fork issue, they won't be going to the beach with me this week for testing. What a bonehead move I pulled on that one by not realizing I had different sizes on different bikes. I was really looking forward to adding take off and hill climbing torque to the front wheel of my dual suspension bike with the 40mph+ direct drive hubbie on the back.

John

 

[tifalou]

I have asked Mr Yao about this motor.
He replied that it is geared, but could not work with 48V.
Disappointing for me, because I have a 48V battery pack. Considering that the Bafang motor can handle 48V, maybe this one isn't a Bafang ?

 

[EVTodd]

I almost ordered one of these yesterday (motor only) since the price is so good but after adding it to my Paypal shopping cart I noticed that shipping is $50. I realize it's coming from China but that's crazy. Kinda reminds me of all the good deals on Ebay.

 

[Drunkskunk]

I'm looking at this kit and my order finger gets itchy. I want it. I need it!

and I need it like a whole in the head. toooo many projects right now, but that is the perfect match for my road bike.

I wonder how these things would do with an RC style controller?

 

[philf]

Any of you guys actually GET one of these in the end?

My itchy PayPal finger went and ordered one last night because I couldn't stand it any more. I went for the motor only (rear) - and I'm interested to know the correct spoke length I'll need in order to lace it up when it gets here...

The stealth value is just too appealing... and this guy's YouTube video would imply that the thing is pretty well executed (he'd made a mistake with the phase wiring on the first attempt to spin it up - this is after he got that sorted)...

[youtube]1P-ln3dmzmg[/youtube]

 

[Russell]

Any of you guys actually GET one of these in the end?

My itchy PayPal finger went and ordered one last night because I couldn't stand it any more. I went for the motor only (rear) - and I'm interested to know the correct spoke length I'll need in order to lace it up when it gets here...

Hey Phil did you get the motor yet?

As for spoke length I found the calculator at http://www.dtswiss.com/ works very well. Of course you need to know a few motor measurements and the effective rim diameter (ERD) of the rim you’re using.

My guess is you've seen the motor drawing on the GM site;

http://goldenmotor.com/hubmotors/hubmotor-R_WHEEL.pdf

but it appears they show the overall diameter of the motor (143.50mm) and not the spoke hole diameter which you need so you'll have to measure it. Also they don't show the flange distance or even enough measurements so that it can be derived from the drawing so you'll need to measure it directly or maybe email them and ask for the crucial dimensions. The ERD is easily obtained from the rim manufacturer's website

I'm thinking about ordering one of the front mini motors so I'm interested to see how your rear mini motor works for you.


-R

 

[aaannndddyyy]

I picked up one of these motor kits S/H a while back its a 350w 48v

it looks to me like direct drive, I could not remove the other cover completely just a few mm but could not see any gears.
http://cgi.ebay.co.uk/350W-ELECTRIC-BICYCLE-E-BIKE-RETROFIT-KIT-MINI-MOTOR-/330441744921?cmd=ViewItem&pt=LH_DefaultDomain_2&hash=item4cefdce219#ht_12853wt_958
part of the add
"New Style, New Motor, New Technology
Mini-Motor, real gearless Motor!!"

 

[Russell]

I picked up one of these motor kits S/H a while back its a 350w 48v

it looks to me like direct drive, I could not remove the other cover completely just a few mm but could not see any gears.

Actually the GM Mini's are 250W Bafangs. I bought a "24V" model from Golden Motor a while after starting this (old) thread. See mine here; http://endless-sphere.com/forums/viewtopic.php?f=6&t=8579&start=30#p195644


-R

 

[aaannndddyyy]

Actually the GM Mini's are 250W Bafangs. I bought a "24V" model from Golden Motor a while after starting this (old) thread. See mine here; http://endless-sphere.com/forums/viewtopic.php?f=6&t=8579&start=30#p195644

-R[/quote]

I had a look at your thread they are Different motors.

 

[Russell]

I had a look at your thread they are Different motors.

I was expecting to get the black case motor shown on the first page of this thread however they changed colors and cases at some point. The Golden Motor Mini however has always been a 250W geared motor. I ordered my Mini directly from Golden Motor and it actually looks like the one they have on their website though I believe they have since changed cases again.





-R