Author Topic: front mini hub motor - off center  (Read 20127 times)

Offline kefa

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front mini hub motor - off center
« on: December 17, 2009, 10:08:44 PM »
hi all,

i recently purchased a GM front mini motor and was surprised to find that what I received did not look like what is on the website and also what others have posted here and on endless-sphere. the fact it looks different wasn't my main issue - the problem I have with what I have received is that the hub is not symmetrical and it means the flanges do not sit in the center. its quite signficantly off center and to use it would mean I would have to build my wheel with it warped to one side. has anybody else received a mini that looks like this?

i got correspondence from tom saying this is a new front hub motor that addresses issues the old where there was not enough clearance for a disc brake. however I don't know why anybody would would want a front hub that is not centered and would be building dished wheels. would like to here from anyone that has received a front hub mini recently.

more pics here on endless-sphere:
http://www.endless-sphere.com/forums/viewtopic.php?f=7&t=14835

Offline Bikemad

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Re: front mini hub motor - off center
« Reply #1 on: December 17, 2009, 10:55:57 PM »
I recently purchased a GM front mini motor and was surprised to find that what I received did not look like what is on the website and also what others have posted here and on endless-sphere. the fact it looks different wasn't my main issue - the problem I have with what I have received is that the hub is not symmetrical and it means the flanges do not sit in the center. its quite signficantly off center and to use it would mean I would have to build my wheel with it warped to one side.

If you take a look at the attached picture you can clearly see the obvious differences.

It looks to me as if the main housing is intended for a rear hub not a front one.

   
                Front                                       Rear


        Your hybrid hub

Alan
« Last Edit: December 17, 2009, 11:15:57 PM by Bikemad »

Offline kefa

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Re: front mini hub motor - off center
« Reply #2 on: December 17, 2009, 11:01:53 PM »
nice job with photoshop Bikemad, thanks.

i thought the same thing but its missing the thread for the gear cassette. the left side of the housing looks very similar.
« Last Edit: December 17, 2009, 11:14:09 PM by kefa »

Offline kefa

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Re: front mini hub motor - off center
« Reply #3 on: December 18, 2009, 05:51:22 AM »
arghh... GM are still claiming this is there new mini front hub. they even sent me a photo of their new hub and it looks totally different to the one I got! its quite obviously as the screws on the casing are different and the flange has a different shape. looks like I might have to go through paypal to try to dispute a refund - very disappointing.


Offline Bikemad

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Re: front mini hub motor - off center
« Reply #4 on: December 18, 2009, 12:08:21 PM »
arghh...

Kefa, try and calm down and hopefully we will get this problem sorted.

I've sent an email to Yao (and a copy to TOM) explaining my thoughts on your incorrect motor, so hopefully we will get a more sensible reply soon.
As neither Yao or TOM have logged on to the forum since you started this topic, they will not yet have seen the photos or this thread.
I'm hoping when they look at the photos and see the actual problem they will be able to confirm that it has somehow been assembled using the wrong housing.

Nobody is 100% perfect, and that also applies to the workers who assemble these motors, so occasionally mistakes are bound to happen!

We just need to be patient now and wait for a response form the nice guys at GM. ;)

Alan
 
« Last Edit: December 18, 2009, 12:13:29 PM by Bikemad »

Offline kefa

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Re: front mini hub motor - off center
« Reply #5 on: December 18, 2009, 08:07:36 PM »
ok. i'll cool off for a bit and wait for a response from Yao... but I was so itching to work on my build over the christmas holidays!

oh well, all for best, my misses wouldn't have been too happy with me spending all my holidays on ebike tinkering.

Offline GM Brazil

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Re: front mini hub motor - off center
« Reply #6 on: December 19, 2009, 12:22:16 AM »
I think this alignment is solved as on this post: http://goldenmotor.com/SMF/index.php?topic=1527.0

Offline kefa

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Re: front mini hub motor - off center
« Reply #7 on: December 20, 2009, 09:53:04 PM »
why - still no response from GM?

Offline TOM

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Re: front mini hub motor - off center
« Reply #8 on: December 22, 2009, 12:12:45 PM »
The front mini motor for 100mm front fork,so limit room
Choose V-brake or Disc brake?

If choose above mini front motor,it can be installed disc brake and be fit for 100mm front fork,the motor isn't in the center,but can fit your rim and make the tire in the center.

If choose old mini front motor,the motor is in the center,you only use V-brake.

Offline Bikemad

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Re: front mini hub motor - off center
« Reply #9 on: December 22, 2009, 03:38:41 PM »
If choose old mini front motor,the motor is in the center,you only use V-brake.

TOM,

In picture "A" the holes for the disc brake fixing screws are clearly shown. So is this a picture of the new front mini motor?
A

Is picture "B" (which is fitted with a brake disc), the same mini motor as picture A?
B

So are you 100% sure that picture "C" (The incorrect looking motor) is in fact a correct and normal new front mini hub?
C
Perhaps someone at GM can kindly explain which of the above pictures are of the "new" front mini motor and which ones are of the the "old" one?

The front mini motor for 100mm front fork,so limit room
Choose V-brake or Disc brake?

If choose above mini front motor,it can be installed disc brake and be fit for 100mm front fork,the motor isn't in the center,but can fit your rim and make the tire in the center.
C/B

In your drawing (the same motor as picture "A"), the motor is offset, but the spoke flanges are centrally perfectly between the forks!
So why are the flanges on Kefa's hub (Picture "C") offset the same way as the rear minimotor?

I still maintain that the main casting on the hub shown in picture "C" has been designed and manufactured specifically for use as a rear hub, which is why the flanges are purposely offset to centre the wheel when used on the rear in conjunction with a different axle and end plate with a freewheel fixing as shown below:




Alan
 

Offline GM Brazil

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Re: front mini hub motor - off center
« Reply #10 on: December 22, 2009, 05:49:55 PM »
Could be a mixed parts motor.... Main case of the rear motor with the closure of the front motor? Could be just an assembly mistake.

Offline kefa

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Re: front mini hub motor - off center
« Reply #11 on: December 24, 2009, 09:06:06 PM »
i believe thats the case as well. but GM aren't willing to own up to it! so now i'm stuck with this motor that is neither front or rear hub.

i popped open the hub to check out the core, it looks exactly the same as the core for a "proper" front mini. so I reckon thats what happened - they assembled the wrong case onto it. GM can I get the proper case posted to me! i'm not happy with this inferior version.

if this is really going to your new front hub - then I suggest people steer clear of it as it is not centered and means you need to build your front wheel dished.



Offline Pullitap

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Re: front mini hub motor - off center
« Reply #12 on: January 31, 2011, 11:39:56 PM »
I also received 21.01.2011 same kind of mixed hub with 26" rim. The rim almost hits the right side of the fork and there is no side clearance for the tire.



« Last Edit: February 01, 2011, 12:35:27 AM by Pullitap »

Offline kefa

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Re: front mini hub motor - off center
« Reply #13 on: February 01, 2011, 12:30:35 AM »
i'm pretty sure this motor is designed for a disc brake. when I ordered mine there was no option to specify you used disc brake or rim brake. I would never buy from these guys again. I ended up building my wheel dished. it works ok but was not what was advertised and was not what I wanted. always a bit of lottery ordering from china.

Offline Pullitap

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Re: front mini hub motor - off center
« Reply #14 on: February 01, 2011, 12:59:39 AM »
How to get it dished?
Is it possible without assembling new spokes? The originals are 2,2 mm thick and 211 mm long both sides. That thickness is not sold commercially in different lengths.