You also- make a thread about this I want a AWD evolve too 
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Tolerance from that drawing should be good for what you are trying to do.
I would recommend a drill press, and using a dowel the rotate the sprocket concentrically.
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The longer your battery wires (to the ESC) are and the further apart they are located, the worse the voltage spikes become. This is due to something called the “inductance” of the wires. It’s present in every wire and every circuit but the high current flowing through battery wires and the hundreds or thousands of times a second the battery current is pulsed makes this part of a setup the biggest producer of spikes.
Each time the current is pulsed and stopped a voltage spike is produced because of this inductance (use your Google-fu for more info). This isn’t much of a problem when you have a low current circuit (headlights for example) that is turned on once when you start riding and off when you stop. But since ESC’s pulse huge amounts of battery current so often this is where the spikes are the worst.
Any amount of current and any length of wire or circuit board trace produces a spike. The longer the wire and the higher the current, the higher the voltage of the spike. This means we need to shorten the battery wires as much as possible and or lower the battery current. Lowering the battery current typically isn’t an acceptable thing to do though.
Another option is to run at a lower voltage or use a higher voltage rated ESC. This does nothing to reduce the spikes but gives a bit more of a margin between the voltage of the spikes and the rating of the ESC. This can help prevent burning out the ESC.
It also helps to keep the battery pack positive and negative wires as close together as possible. This allows the magnetic fields generated by each to cancel themselves out, reducing the overall inductance of the wiring. This reduces the magnitude of the spikes.
Our last defense against spikes is to try to “swallow” them using capacitors, which are very efficient at this. This is what you see every ESC doing and is critical for the survival of the ESC.
We often can’t reduce the length of the battery wires or run them together for their entire length. We often can’t reduce the battery current, lower the battery voltage, or use a higher voltage ESC. This means spikes are there and our ESC’s are vulnerable. The only thing left is try to stop the spikes that are there just before they get to the ESC circuitry.
Caps at the battery end of the wiring or along the battery wires are a waste since spikes can still be created between those caps and the ESC. Keep the caps at the inputs of the ESC.
Most ESC’s already come with caps that will do the job but very long battery wires or setups that run right at the ESC’s voltage rating might benefit from additional caps being used. The caps need to have very short leads and added using very low resistance connections, otherwise they are useless at swallowing voltage spikes. The caps also need to be very low resistance themselves. i.e., they need to be “low ESR” caps, to work well and need a high enough voltage rating.
Folks here will be glad to help if you need recommendations. Just describe in detail your setup and your concerns.
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My battery will only charge to 47.46. So I took it aprt and measured from the balance plug
- 4.09
- 8.17
- 11.74
- 15.70
- 19.80
- 23.67
- 27.77
- 31.87
- 35.67
- 39.76
- 43.37
- 47.46
is this a balance problem or something more?
Visually the pack looks good.
Thanks for the explanation! Greatly appreciated 
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It’s very likely the first 6 cables you grab are all charge-only.
Most cables are charge only, because they’re cheaper to manufacture.
I suggest you specifically buy a “data” or “sync” cable if you have doubts.
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Well, it is definitely far out of balance.
Fix that, then see if anything else pops up.
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Thx, any ideas how to do this with a Imax b6 charger…it’s the only balance charger I have.
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Set it for 1S and connect only that P-pack
I’d charge it slow at like 1A or less. It’s at 3.5V so you’re okay but if it was down into the twos like 2.5V then I’d start at like 50mA charge LOL
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should I charge it (number 3) to 4.09V?
I would
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Once you get it all balanced and charged, when you begin to discharge it again, stop and measure them again. If p-pack 3 is draining faster than the other ones, then you’ll have to snip it out and make it 11S battery
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any suggestions as to how to connect only that P group for charging. Would this work charging from the balance plug.
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I use those alligator clip things
And that harness, yes
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@Boardnamics told me that the bolts are 3/8" UNF. 2.5" long. Grade 8. So maybe looking at McMaster Car as mentioned above could be a solution. Don’t know if anyone else knows where to source them?
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if you made a thread there would be a good place for this information to live, and be easily found in the future.
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that is how I do it with two jst pins
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Yes, that should work.
Just go through and get every group to the same voltage. Could be full charge (4.2 volts), or storage charge (3.6/3.7 volts), doesn’t matter, as long as they’re all the same.
Fastenal is also a good place for anything hardware related.
I once needed a 21mm reverse threaded bolt, and had it in hand the next day. I’m 2 hrs from headquarters though.
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+1 on them
And it seems funny but they are Fast. Not as fast as McMaster-Carr though, they’re like lightning.
edit: oops, I’m referring to Fastenere
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