The helpful 9C wire upgrade thread, explicit DIY pictures.

h0tr0d said:
Why aluminium wire?
Wouldn't copper be better for this particular application?
liveforphysics said:
wirestraighten.png
Click to expand...
Click to expand...


I don't use aluminum wire for anything, that's either silver plated copper wire or tin plated copper wire. :)

Also, I've started thinking using enameled magnet wire might be the better to use just for an extra layer of protection from chaffing related shorts over time (though if it's stabilized from moving well with silicone or epoxy it should be fine this way).
 
liveforphysics said:
h0tr0d said:
Why aluminium wire?
Click to expand...

I don't use aluminum wire for anything, that's either silver plated copper wire or tin plated copper wire. :)

Also, I've started thinking using enameled magnet wire might be the better to use just for an extra layer of protection from chaffing related shorts over time (though if it's stabilized from moving well with silicone or epoxy it should be fine this way).
Click to expand...

Silver = more electrons, tin = less and enamelled = 0 electrons... I'll probably just go with 2,5mm^2 with thick insulation, cheap and aprox. double the copper.

Have you got any idea how calc the energy eff boost from such a mod?
 
h0tr0d said:
Have you got any idea how calc the energy eff boost from such a mod?
Click to expand...


I can make an example, and you can scale it up or down as it suits your application (like if your wires are longer or shorter etc).

If we've got an RMS phase current of say 25amps, and we're using 1m of the factory 16awg wire, then we've got ~39mOhm of wire under a 25amp average load, which would be ~24.8W of power being wasted in heating the phase wires.

In the same setup with 50amps RMS phase current, you're looking at 99W of power being wasted heating phase wires (and melted wires if you're trying to do it continuously).

If you upgraded to 1m of 10awg wire for each of your phase leads (~9.8mOhm combined), your heating at 25amps RMS will be 6.15W, and at 50amps RMS the heating will be 24.6W. (and more importantly, not melted and burning up)

So, for a very low powered bike (25phase amps average), you only save about ~18W, and for a little more powerful bike you're saving about 75W, but more importantly you're not doing a walk-of-shame home from melted phase wires.
 
As an update to the advice about drilling out the axle. Do so with extreme caution. If the drill bit is not dead on and runs at an angle you can destroy the axle. I wouldn't do it again with out a drill press. I did it with a hand drill and it wasn't straight enough. My bad. After a few months the axle snapped popping a curb. Thank fully I had dual clamping drop outs so the wheel didn't come out, but It was an impressive display of sparks as the controller shorted out.
 
LFP,

Nice, thanks!

Battery amps to phase ratio? probably not linear... Consider 3x larger?
meters of cable of controller to motor x2, wire in and out, right?
Is the controller always supplying to alternating phases? no "off" time waiting for the hall sensor detect new phase?

Mechanical guy trying to learn electrical stuff... :mrgreen:
 
http://www.endless-sphere.com/forums/viewtopic.php?f=2&t=19590&hilit=current+multiplication
Found it!! :lol:

h0tr0d said:
LFP,

Battery amps to phase ratio? probably not linear... Consider 3x larger?
meters of cable of controller to motor x2, wire in and out, right?
Is the controller always supplying to alternating phases? no "off" time waiting for the hall sensor detect new phase?

Mechanical guy trying to learn electrical stuff... :mrgreen:
Click to expand...
 
salty9 said:
Liquid dish soap makes a good rinseable lube. It or something similar is used to lube the bead when changing tires.
Click to expand...
If you keep Xanthan gum around in the kitchen for thickening stuff up, it is also slick when wet, sticky when dry, and water soluble/wash-off-able.



FWIW, you can also use it mixed up thickly as a paint mask--brush or pour it on, let it dry and then wash it off when you're done painting. you can even cut it with a razor if you are careful, scoring it and peeling it up from areas you want paint to stick to, then airbrushing or painting the surface however you want.
 
@the original post. These are the kind of write ups we need here on ES! We need a library of these... I hope its listed in the wiki.
I'm looking at making a guide about liquid cooling a 9C.

Does anyone know a source for 9Cs or MACs with already upgraded phase wires? Cell man is out of stock of the upgraded MACs.
 
love this thread. Did this with 12 AWG and definitely not easy. Thanks LFP!!!!

phases009_zps01594b0e.jpg
 
The Stig said:
Yungyakz said:
Hey mate is there any way I can see the photos?
Click to expand...

Welcome to this historic forum! And a thread full of ebike legends.

I think more details are needed, like: Who are you talking to? what photos? what are you trying to do?
Click to expand...

The photos on the first post. All gone.
 
A while back, there was a website update, and some of the picture-hosting websites no longer provide link access to old pics.

Here is a link to an ES thread where a Bafang BPM is disassembled, and the phase wires doubled through the axle.

Be aware, as soon as the fattest possible phase wires are identified and installed, there is a cooling benefit to making the phase wires even fatter just a few inches outside the motor-shell.

Copper is also a great heat conductor, and the phase wires outside of the motor can be used as a heat-sink.

https://endless-sphere.com/forums/viewtopic.php?f=16&t=51237#p758156
 
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