I’m curious as to what gearing you’ll be using these and wheels and 13s?
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Tim ? he told me 2:1 ratio on 111mm with 14s this time 
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I always have something up my sleeve…
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@Riako I’m confused as hell about what you’re ordering.
If it’s 6396 motors, “sealed” then I’m down for 2. Lower kv the better. I’ll await your group buy thread?
Same. 150KV or lower. Anything above that won’t work for me.
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Yes I try to make one here :
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@Riako may I ask you what ratio you are going to use with a 130kv motors. I bought 150kv 6374 motors to use on moon gear drive I think it is 1:4.49 or something. But later I read frank saying that higher Kv and higher ratio was more efficient, less heat his suggestion was 190kv with 1:7 gear ratio. I am a bit confused.
Mostly, and my fav., 4.67:1 (9x42T chain) on 9", at 70amps batt and motor max, 12s 12Ah graphene, from +22Wh/km (-20km), to (don’t have nb in mind but) +40km.
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What is more efficient?
58kv motor with 1:1.79 ratio
or
130kv motor with a 1:4 ratio
or
170kv motor with 1:5.32 ratio?
or
220kv motor with 1:6.77 ratio?
(Weird ratios to make the wheel speed equal)
My understanding (and past discussion) was that changing the kv is better than having a high gear ratio because belts + pulleys have more efficiency losses
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I’m really not a motor concepter, or the master builder or a Professor ^^
I just choose them to get big motor with high torque and “high” ratio for off-road.
Low kV is supposed less max amps (so maybe less heat).
I like to be able to use a small ratio compared to 190kV or more.
Like I did, making big chain drive with 140kV 5065 Racerstar on Berg.
Or like the Nano urethane Gear Drive with custom adaptor to use Bergmeister 150mm.
Now 3Dsas sell the same.
And, don’t ask me why, but I like to get the wheel gear diameter close to the rim diameter 
isn’t it perfect ?
This will looks even better on 9" …
Edit : Also, about saving effeciency, we could maybe say that low kV = less drive/motor/and gear wear ! If I compare in my case same setup using 170kV or 190kV the all gear drive and motor (so bearing etc) will make more turn, so more wear…
Maybe, in my case again, same with battery, as low kV = a bit less max amps, so battery works easier than I set higher max current to get the supposed same torque …
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You however have accumulated experience from riding and building board for a long time so I’d be inclined to trust your feedback.
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Cool question. Assuming the motors all have the same amount of wire inside they will produce the same ratio of heat in the windings to torque and said to be the same km. ur better with the biggest gear u can fit and highest kv, Infinitely so except there’s both the gearing losses, which need not be much if it’s an efficient gearing, but more so the limit there are the iron losses(hysteresis and eddy currents) which rise with increased electrical frequency.
. The point at which a bigger gear would be less efficient depends on how the motors are used but the common 3:1 ratio results in much more copper losses than iron and a bigger gear would be an advantage.
Most efficient would be a gear so big that the iron and copper losses are about equal.
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These have 10mm shafts right? I wish the spiral bevel gears worked with 10mm I would jump on these.
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I think I may use these on chains as well. 13s 9/42.
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Interesting. Thanks!
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if all the motors have the same size constant (km), then the highest kv motor that is geared for the same top speed will be most efficient for the same acceleration or constant speed.
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Might be able to find a bevel gear with 10mm bore assuming the kit uses a standard size
True.
@murdomeek i should add that above a certain kv, the motor will be spinning so fast that iron losses will become so significant that the logic of higher kv for more efficiency only extends up to a certain point. and iron losses are hard to estimate but with high enough kv they will exceed the resistance losses.
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The KV possible for this motors because the position of outgoing wire is fixed position, can’t just wind half circle wire is limited. It Can be ~100, 140, 180, 210, 250.
@3DServisas made a great adapter for this motor:
Needs 260 Hanger for them to fit, and on some gearings need 275mm hanger.
Also made a special cnc made baseplate to prevent motor hit them if using 260mm hanger:
Looks great with this wide motors:
You can order the gears and hanger on @3DServisas webbshop now and i recommend to prevent any problem get the 275 hanger.
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