Cable frayed at axle - removing non-drive side cover from Magic Pie I?

[Herkell]

Hi all,

I just searched this forum for how to do this, and got no answer to my specific question. I bet there's a post buried here somewhere, so please direct me to it if you know of it!

I have a Magic Pie (the original) with a damaged cable leaving the axle.

I'm planning on replacing all wires - wahoo! I opened up the drive (right) side with a gear puller, and saw the controller - but need access to the other side to get at the wires that need replacing.

It looks like there is very little clearance between the axle and the side cover on the left side - not enough to pull a complete cable through. Do you need to simply run the wires individually, and feed them through this little gap as you put the motor back together?

I've attached a picture of what I'm working with.

If it's a really difficult repair, would you suggest simply trying to do what I can from outside the motor?

Thanks in advance for your help! I'll be away for 3 days, so don't worry if you don't hear back for a bit.

-H

[Bikemad]

Check out Magzy's post which shows how to remove and refit the cable while replacing a wheel bearing.

Magzy's Pie had an external controller so the wires were left connected at the hub end and the cable pushed from outside in through the slot under the bearing, but with the internal controller you will need to make a note of the connections on the controller and then unsolder all the wires from the controller (except for the five hall sensor wires) and then gently feed the wires from inside out through the slot under the bearing.

After looking closely at you photo, I would say your wheel has been modified to connect to an external controller.
You might want to have a read of this post describing how to fit new wires to connect to an external controller.

Alan
 

[Herkell]

Thank you for the quick reply Alan!

This wheel doesn't use an external controller - why do you say that?

Thank you for the link. Yes, that helps with my overall understanding of the motor and job at hand! Looks like I'll have to completely take apart the motor - both side covers, and the stator too. Then I'll cut all wires going out of the axle, pull them out, and resolder new ones in their place. I'll then carefully rethread these new wires underneath that bearing, and push them out individually. They won't be encased as they leave the axle (just 11 separate wires), but I'll add heat shrink as early as I'm able. And maybe epoxy where they leave for extra protection.

Sound about right?

There are 11 wires - two big ones (red and black, to battery), and 9 smaller ones of various colors. The brown is completely severed, and others are frayed - but no shorts yet.

Let me know if there's anything I should keep in mind as I proceed, and thank you for all the help. Alan, you're great!

-Henry

[Bikemad]

This wheel doesn't use an external controller - why do you say that?

It looked like three wires going to a connector just after they exit the axle which made me think that it might have been modified before.

Let me know if there's anything I should keep in mind as I proceed

Just make sure that all sharp edges are removed from the slot in the axle to prevent your new wires from being chaffed through.

Has the axle has spun and damaged the wiring, or have you stripped back the casing to reveal the separate wires shown in the photo?

Alan
 

[Herkell]

Hi,

I attempted the repair today - what a project! The disc brake side's bearing was totally rusted to the axle, so I decided to cut the wires 2 inches from the bearing and resolder them from there - but when I put it back together, there wasn't enough of a gap between the axle and the side cover for the soldered (and therefore bigger) cables.  See 1 of the attached pics for exactly what I did, and what NOT to do in the future!

I ended up cutting the cable on the non-drive side, carefully threading new wire under the bearing and up to the cable, and connecting everything there. See the other pic for this.

After careful reassembly, I turned it on and... everything works except the ebrake! I was told by the original owner that the red button on the throttle engages the ebrake. Cruise control, battery LED's, and throttle all work fine.

Any idea what might be causing this? I was careful to properly solder together all wires except for 1 - an olive-yellow wire that wasn't connected to anything on the controller.

I noticed that one of the pins in the connector to the controls (throttle & cruise control) is shorter than the rest. It's one on the perimeter - according to http://the-electric-bike-company-forum.1057686.n5.nabble.com/Welcome-to-the-Discussion-Area-for-Electric-Bikes-td4582413.html (scroll down), it therefore wouldn't correspond to the ebrake. Also (and I was able to get a poor quality picture of this) the female side of the connector to the controls has some corrosion.

Thanks again for the help!
Henry

[tbiceman]

Having the same issue with an mp2. Gotta be a better way to do this wiring to make it last. Anyone?

[tbiceman]

2 quick questions. Will the mp3 cable ($39.00)work for the mp2?  And how do I get the cover off the mp2? Sorry im npt more mechanical but after cutting a hunk out of my thumb on the axle, im not going futher without some guidance. Do know my dremel tool will be going to woek on thay axle slot tho(lol). Thanks.

[Bikemad]

It should be possible to use the MPIII cable but I don't know whether the wire colours will be assigned to the same functions.

Unfortunately, you would also need to replace the front harness and all the controls (throttle, brakes and cruise) as the connectors are different too.

If you have enough length remaining on the old motor cable it might be possible to cut it at the damaged portion and feed it into the motor and rejoin the wires to the existing wires inside the hub.

Check out this post for more details on removing the side covers.

Alan
 

[tbiceman]

Great, thanks. Will give it a go once my thumb heals up

[tbiceman]

Removed the hex bolts on both sides, removed top spring clip. Every thing loose but will not release. Should I try a bigger hammer? On the other end of the axle, of course??  Also doe anyone know where I can get a free wheel tool since Canadian site says not available?
Ken

[Bikemad]

A bigger hammer sounds good to me, but thread a nut on the end of the axle until it is flush with the outer end of the axle.
Used a hard block of wood to absorb the shock of the hammer as you don't want to deform the end of the axle.
I use a large rubber mallet.

The freewheel should come away with the side cover and does not need to be removed separately.

Alan

[tbiceman]

Thanks for the quick reply Alan. Just wondering, do you ever sleep or do you just monitor for my stupis questions 24-7.

Ken

[Bikemad]

Just wondering, do you ever sleep or do you just monitor for my stupid questions 24-7.

Sorry Ken, I'm afraid that I cannot disclose the exact details regarding my sleeping habits, but needless to say, when I'm not awake I tend to spend the majority of my time asleep.

Alan
 

[tbiceman]

There is no way this cover is coming off. It comes out about an inch, to bottom of axle threads and binds solid. The axle must be warped or the bearing is, so I guess I'll be retiring this motor. If I get it pressed off it will never go back on, so guess it's time to upgrade to mp3 or vector if it comes in 1500 watt config.
Thanks for all your help on this Alan. Will be in touch once I get the new motor.

Ken.

[Bikemad]

I had chance to quickly try my MP4 last night and I had it set to the maximum battery amps (30A) and I recorded a maximum of 1449.3 watts on my Turnigy wattmeter and the maximum recorded current was 30.28 amps at 48V.



I have replaced the old MPIII rear wheel on my DIY chopper bike with a new MP4 and it is noticeably different to ride compared to to the MPIII.
The MP4 is a lot more responsive to the throttle and with the increased torque, I was forced to reduce the acceleration setting so that I could pull away from a standstill without lifting the front wheel every time. The old MPIII would only lift the wheel when I applied pedal force as well as full throttle.

The torque is really impressive and I genuinely could not hear any difference in the motor (apart from its speed increase) whether the throttle was opened fully or completely released. Applying the throttle does not produce any discernible noise.
The obvious pinging noise under load that the MPIII produced seems to have been completely eliminated on the MP4! 

Alan