Pedelec working randomly when pedeling.

[manmark]

Hallo everybody.
I bought a MagicPieII a month ago and I just managed to install it but several thinks came up after I ride it for a while.
One of them is the pedelec asistance.
It seems to work total randomly when I do pedal. I checked everything I found in this forum and seems that I have install it right.
The other thing about pedelec is the settings in CC what exactly means for low middle or high at PAS section?
Thank you in advance.

[manmark]

Hallo again
I also notice a growing lose of the axis of the hub how can I tight it? is the same way as normal hubs or do I have to open the magicpie?
Also for your information the PAS sensor seemed used as it arived to me; could that have anything to do with the problem to my prevews message?
Thank you in advance. 

[manmark]

About the problem with the lose I mean the bearing of the hub not the spokes.

[Leslie]

Sorry

The problem you have provided is a difficult to understand.  The english is not easy.

What is your language.  And can you provide a .jpg picture of how the hub is growing lose.

I am thinking you have made axel nut is very tight but the hub is growing loose and moving to side to side?

[manmark]

The problem that I describe is that my hub seems to have lose at the bearings I can't explain it more easy than this. I can push the wheel vertical to it's level and the hub seems to lose 1-2 mm at it's axis. Spokes are tight so the problem is not from there. The point is that if something happened to the bearings do I have to open the hub to check and change or this loose is normal? (I show it to a bicycle repair centre and they told me that it is loose). What can I do? On a normal hub you just tighten or change bearings. Please advice.

As for the pedelec it is not giving me continuous power when I do continuous pedal, just randomly when it decide it, very useless and dangerous, it seems like  the sensor have random response which is not true because everything seems have installed right, maybe sensor is faulty? how can I check it I tried everything I found in forum..

Sorry about my English.
Thanks.
 

[Leslie]

I cant remember so well but I have pulled two MP's appart and there are circlips inside that holds one bearing and the hub from moving right, if looking from behind the wheel.

You need to pull it appart and investigate.

A sollution maybe to wind a solid layer electrical tape on the axel before this bearing just a little bit more out than where this circlip should be working, when you bolt the face plate can back down tape around the axle pushes the bearing into its seat with much pressure. 

As I said I cant remember its been a year since I did this but I removed all the circlips on the right side of one hub, even the circlips holding the wires down as my constant fiddling I had found the sharp circlips cutting into the wires. I use electrical tape very tight and then I used heat shrink to make it look neat.  I will see if I can find some picture of this.

[Leslie]

Here is the damage that needed to be repaired.  Looks like I got lucky and caught it it time.



I used an old file and sand paper to smooth it up.




Here is a pic of the stator finished rewiring,



This holds wires in, and see how it holds the bearing into place, the same thing can be done on the other side.  When both bearings are held in place from moveing around, and more so on the other side, the hub the face plates can clamp the wheel into position.  I think the other side of this picture, the bearing does sit out a little bit from the stator and bearing is held by a circlip.  IMO this idea is an improvement.  And this hub I have been using with no issues on both wires and not using circlips to hold the bearings from moving. 

If you put the roll of tape in between the left bearing and stator it will stop the hub on the bearing from slipping a little to the right.

When I bolted this plate down I had to push the face plate down with bearing to compressed the tape between bearing and stator.  After bolting it is sold for over a year.

[Bikemad]

I show it to a bicycle repair centre and they told me that it is loose

Is the hub just sliding sideways on the axle as indicated by C, or is there vertical movement on either side as indicated by A causing a twisting movement as indicated by B or perhaps it's a slight combination of all three?



If the movement is only as shown by C, I'm guessing that the hub could have been assembled without the wavy spring washer that is supposed to prevent any free movement of the hub along the axle.

The wavy washer is similar to the one shown in this picture:



If I remember correctly, mine was fitted on the freewheel side of the hub and went between the machined bearing face of the axle/stator and the innermost side of the bearing.

Alan
 

[Leslie]

Manmark

I you go into the motor to repair, could you take some photo's o this problem while you are inside the motor and share with us.

Pictures can help others and help others her help you.

Thank you.

[manmark]

Well... Hallo again.
Thanks for the quick response.

First: Dear Les no I didn't yet got in to the motor; I am waiting for an answer from Bikemad below.

Second: Dear Bikemad no the movement is not C, the movement is exactly A and B; obviusly together.

I will appreciate any advice for the problem.

Thanks.

[Leslie]

Well... Hallo again.
Thanks for the quick response.

The movement is exactly A and B; obviusly together.

I will appreciate any advice for the problem.

Thanks.

 

A B is like a a bearing failure,  or the bearing seat is cracked.  Maybe.  I would guess a bearing failure would make a lot of noise.


Rear suspension FTW.

[Bikemad]

As the wheel is new, I think the movement is unlikely to be due to a bearing failure, and I would say it is due to a less than perfect fit between either the inner races of the bearings and the axle or the outer races of the bearings and the machined recesses inside the cast side housings.

Bearings are usually manufactured to pretty exact sizes, but the machined sizes of the axle and side covers are probably not quite as good as they could be.

Ideally the bearings should be nice a nice snug sliding fit onto the axle and inside the casing, this is sometimes referred to as a transition fit.  If there is more of a gap between the bearing and the axle (or side casing) it produces a clearance fit which will inevitably allow some unwanted movement.

Due to the large size of the wheel and the close spacing of the bearings, a small amount of clearance on the bearings will result in a much larger amount of movement at the rim.
For example; if the axle was machined just 0.1mm (0.004") too small and the bearing recess in the side casings were machined 0.1mm (0.004") too large, this would combine to give a total amount of 0.4mm (0.016") movement at the hub, which would probably produce around 1.6mm (0.064") of sideways movement at the rim. Any play within the bearings themselves would obviously add to the total amount of movement.

These hubs are not manufactured to aircraft standards, and are bound to have a certain amount of play when they are fully assembled.

To eliminate the movement completely would require the axle and housings to be machined to within a very fine tolerance, resulting in an interference fit, which would then require the use of an hydraulic or mechanical press to assemble the hubs. Disassembling the hubs would then be virtually impossible without the use of purpose made pullers for removing the side covers from the bearings and for extracting the bearings from the axle.

Manmark, I would suggest that you carry on and fit the wheel to your bike and try it out, as the movement you have noted is unlikely to have any major affect upon the operation of the wheel, especially when you have some weight pushing down on the axle as well.

Alan
 

[manmark]

Dear Bikemad I agree with you in every way; You seem to know the subject very well so I will follow your advice; and I hope that the lose will not grow. Thank you very much and for now I am not planing to open the motor as it works well; except I would like some more torque for climbing and I wonder if I can get some if I overvoltage; or this is only for speed? Unfortunately I made my purchase a month earlier than MP3 was announced.

And also is this other thing with pedelec. Is it ok that I have rundomly assistance from PAS and not continiusly as I pedal?

[Leslie]

LOL 

My MP is is solid as a rock, and I can get it apart.  This movement being reported in my five years using GM Hubs is new to me.  I would not accept any of this "growing loose"without checking.  You reported "growing" and I would never advise, probably, might, um lets just to see what happens. Another 1-2 ml vertical movement can lead to stator hitting the magnets, magnets breaking, wheel jamming, massive failure and an accident..   Some people don't just take a nice ride around the local park on the occasional weekends to take the doggy for walks.

I have women and children ride my bike also.

As for PAS remove it, it is only or retards that need feet to make a hand throttle work, like WTH?. 


Over volting, Give your self an extra 12v and an extra 10km/h and it will convert back to torqe on hills alrighty. thats the way induction converts in electric motors under a load im sure others will say it doesnt..


A new standard is allowed to be lowered every time I come here, until one day it results in someone getting hurt.

Any way its your life.  Enjoy.

[Leslie]

Just look at the clearance betwwen stator and magnets. 

It is too small for a growing verticle movement between the hub bell-magnet rim; and stator. 

What would happn if the stator is allowed to bang hard on the magnets when going fast and hitting a big bumps and pot holes? 

At least would be a lot of load on the controller on the impacting events, damage to the stator, maybe stator former getting picked up between two magnets and chewing throught the whole hub. or generarted friction heat between stator and magnets, magnet expands from heat and cracks locking wheel to a hault. 

I think the good God or Devil is left to decide the prognosis.