Best 250W HUB motor (small, light & freewheeling)

[evaleto]

Dear All,

I'm wondering which motor in the following list is the best choice for my specific usecase. I'm building a kind of ebike with the usecase similar as the nano technology from (http://www.electricwheel.co.uk/). My specifications are: Small battery 10S2P li-ion panasonic with max load 14A. I planed also to build an opensource small controller with the DRV8332 driver for BLDC and arduino for the software. Finally, I'm looking for the smallest and best motor. For the motor I got one to do my prototype but I got some issue with it (eg. my previous post). Is there anybody that knows more about those differents motors (or others not in the list):

For my needs, the most keys are 250W, <3Kg, freewheeling
==================================================
http://ebike-bmsbattery.com/dispro.php?id=55
http://www.bmsbattery.com/front-driving/299-250w350w-q-85100sx-motor-e-bike-kit.html
http://www.tongxin.net.cn/en/parameter.htm

Cheers,
Olivier

 

[evaleto]

an other 250W motor with a very good freewheeling quality, (specs are missing):
http://www.szbaf.com/proshow.aspx?id=73
http://www.youtube.com/watch?v=y9BeZW79JZU

 

[blueowl]

I look for a lighweight motor as well. I am for just assist motor (not running all the time).
And sadly, after I had read many posts, it seems to me that most of the motors have a drag that is *not* negligible. The exception seems to be the tongxin.
However, that is probably very hard to get. Does anybody know any cheap source of it (best in Europe)?

A discussion about freeweeling:
http://www.pedelecs.co.uk/forum/electric-bicycles/4607-brushless-hub-motors-have-freewheel-3.html

 

[kriskros]

try cell-man for geared motor...free wheel ,no drag....about$150.00 or lessw

 

[evaleto]

I look for a lighweight motor as well. I am for just assist motor (not running all the time).
And sadly, after I had read many posts, it seems to me that most of the motors have a drag that is *not* negligible. The exception seems to be the tongxin.
However, that is probably very hard to get. Does anybody know any cheap source of it (best in Europe)?

A discussion about freeweeling:
http://www.pedelecs.co.uk/forum/electric-bicycles/4607-brushless-hub-motors-have-freewheel-3.html

You are the one someone knows where to order this motor ?

 

[neptronix]

The best freewheeling hub motor i know of is the MAC, but it is not what you would call light; it is about 4kg or 9-10lb.

The 'nano technology' motor is actually a tongxin which does indeed meet your specifications.

Here's a tongxin thread:
http://endless-sphere.com/forums/viewtopic.php?t=340

There are more though. use the search.

 

[neptronix]

By the way, the cell_man motor kit is a really great deal. Not the best freewheeler out there but it does well.

[youtube]HY7lBtPgoIk[/youtube]

 

[blueowl]

I'm still searching a source for a tongxin motor. I have contacted http://www.b-t-n.cn and they offered me their mini motor 114
(http://www.aliexpress.com/product-gs/387007963-Electric-bike-front-wheel-114-mini-motor-wholesalers.html). Does anyone happen to know it, has more info about that motor?
What is quite crutial for me is a very good freeweeling. I really want to be able to ride my bike with motor switched off without any noticable drag and only use motor uphill. Bike should be bike, not a moped
So again, could anyone recommend a place where to get a tongxin? Or are there any alternatives to it in regard to low noise and low drag?

 

[PetriK]

I only have experience of two geared hub motors, but is there really difference in frewwheeling ability ?

The basic design is the same meaning that there is three reduction gears bringing about the same loss. No significant differences between different bearings.

Am I missing something in the equation ?

 

[blueowl]

I only have experience of two geared hub motors, but is there really difference in frewwheeling ability ?

The basic design is the same meaning that there is three reduction gears bringing about the same loss. No significant differences between different bearings.

Am I missing something in the equation ?

There is a difference. Most of hubs have the same design and use planetary gears. But the Tongxin seems to be a bit different; it uses friction metal rolers. See nice description at
http://www.pedelecs.co.uk/forum/electric-bicycles/4607-brushless-hub-motors-have-freewheel.html#post58388 and search the forum.

And here is a real experience comparing Bafang and Tongxin: http://www.pedelecs.co.uk/forum/electric-bicycles/4607-brushless-hub-motors-have-freewheel-3.html#post58536

 

[GrayKard]

Here's some info on the freewheeling of the Q85 motor: http://endless-sphere.com/forums/viewtopic.php?f=3&t=14109&start=97

Gary

 

[evaleto]

I'm still searching a source for a tongxin motor. I have contacted http://www.b-t-n.cn and they offered me their mini motor 114
(http://www.aliexpress.com/product-gs/387007963-Electric-bike-front-wheel-114-mini-motor-wholesalers.html). Does anyone happen to know it, has more info about that motor?
What is quite crutial for me is a very good freeweeling. I really want to be able to ride my bike with motor switched off without any noticable drag and only use motor uphill. Bike should be bike, not a moped
So again, could anyone recommend a place where to get a tongxin? Or are there any alternatives to it in regard to low noise and low drag?

I got motor and controller here http://www.h9.com.cn/ The motor is a tongxin (200W for 83mm fork) and the controller is the LSW70A (max 250W 14A).I choose the tongxin for the freewheeling. I will also try the bafang (from 8fun) if I can find one for 83mm fork.

olivier