gmac harness

[Chrisheuer]

ok here is a short saga!! Making a christiana type ebike for me and my disabled daughter. I've changed frames to a worksman front load frame things are going well motor is working Gmac I'm zip tying down cables give it a test and one little pop back by hub and it appears i've stripped the shield the motor harness. after removing the hub and trying the motor again with the cable not bent it runs but as you can see from the pic it is ripped to hell! Ive looked at the grin videos about disassembling the gmac and replacing the harness. nothing looks fun or easy.
Questions
it appears only the small orange cable is severed one of the larger wires is appraised is replacing the cable harness the only fix.
when putting the torque arm on I had trouble getting it in a position where it wasnt slightly pinching the cable with may have lead to this.
Ive been working on this bike for years now, I'm not one to giveup, I'm wondering if the group knows any body in the columbia mo area that works on ebikes ?
Is harness replacement on a gmac a hard task?

 

[offGridDownUnder]

it appears i've stripped the shield the motor harness

Can you say if the damage is due to the motor pulling the cable, or due to nearby parts cutting the cable?

The green/aqua wire appears to have damage as well consistent with being cut or gouged. The picture does not show a disk brake rotor - instead it appears the spacer and bolts are still installed. If you don't actually have a rotor on that wheel, you can/should remove the spacer - but I think you'll want to install shorter bolts to prevent water entering the motor.

If no rotor, there is no reason to have moving parts so close to the cable, so you may gain.

As to the work, it's always hard the first time. Pace yourself. Given what you've accomplished, you can certainly do it. Given your 'payload', I would not want to risk a cable failure away from home, so I would replace it.

 

[Chrisheuer]

Can you say if the damage is due to the motor pulling the cable, or due to nearby parts cutting the cable?

The green/aqua wire appears to have damage as well consistent with being cut or gouged. The picture does not show a disk brake rotor - instead it appears the spacer and bolts are still installed. If you don't actually have a rotor on that wheel, you can/should remove the spacer - but I think you'll want to install shorter bolts to prevent water entering the motor.

If no rotor, there is no reason to have moving parts so close to the cable, so you may gain.

As to the work, it's always hard the first time. Pace yourself. Given what you've accomplished, you can certainly do it. Given your 'payload', I would not want to risk a cable failure away from home, so I would replace it.

hi and thanks I would say it is caused by near by parts cutting the cable. There will be no rotor so Ill look into removing the spacer. Thanks for the encouragement.
Chris

 

[Chrisheuer]

Hi until I get a new cable for the gmac I've had some success possibly fixing the existing cable. I was able to solder the small orange cable which is apparently a thermostat sensor. I amusing some liquid tape and silicon tape to rebuild the cable. As you can see I have taken off the rotor spacer but have not put the bolts back in. There appears to be enough space / depth for the original bolts to go back in but in the interest of caution I plan to get some shorter bolts to replace the original ones.
One thing I have noticed is that this new worksman frame I'm using has the very long drop out slots compared to the bridgestone frame I used on the original build. The drop out slots flared out more to allow more room for the cable to exit. see pictures. I'm wondering is mounting the axel close to the opening of the slot would be bad or possibly modifying the slot to allow a little more room for the cable to exit would be better. I guess my thoughts have allows been that the axel should seat all the way down in the slot for stability. Any thoughts on this?? The motor is running now the question is can I get it mounted back on the frame with the torque arm without messing it up again.

 

[DaLanMan]

Well it appears that you have a problem, it appears you have a screw or 6 on the loose...