@BenjaminF basically the axles just have flat spots to keep the stator from spinning with the motor. The problem is most bikes are aluminum and it’ll just shear the aluminum so the axle spins. Here’s a little diagram. They are NEEDED on fronts so your wheel doesn’t fall off after shearing your forks drop outs. But It’s only needed on the back if you use a lot of power
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Dang shipping to north cali is 44 bucks… boooooo
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Has anyone actually rode the bikes these are on? 36v seems like id want more power.
Maybe ill do a duel front tire. 
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wtf $0.10/cell. I know nothing about these cells, but 14500 is AA size, and 750mah is about the normal capacity. Can be fun projects with AA battery holders. Overclock your flashlights (this is actually a thing).
I don’t know what the hell that thing with 4 bike wheels is but I’m in.
Yeah, they appear to be Jump bike kits.
In the Jump package, they are dog heavy, but get you up to their 20mph top speed pretty quickly, and climb 20% grades w/o a sweat at full battery. Can get the wheels to slip if you try hard enough. The one that I rode that seemed to have its limiter removed was hitting low 30s before there wasn’t enough power to push it faster.
They’ve got to be under-driven, since they are used and abused in a rental fleet. From my observations, the ones here in Denver lasted about 18m of hard abuse before a good number of them started dying.
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Yeah, you could probably build a bad-ass pedi-cab with these and make some good money (once the Rona scare dies out…)
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18m as in 18 months?
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Really hope these are from bikes with failed electronics and not failed hubs…
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Yep. So, like 5-600 cycles. I couldn’t tell you what was going wrong with them at that point, other than it had to do with the drivetrain, and not the other mechanics of the bike.
At this point, 2 years later, they’ve all been replaced by an updated model.
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Probably all the ones that were thrown in the bay by pissed off pedestrians. 
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I just went down the street to an e-bike hub here in SF…looks like all the Lyft branded bikes are front and rear hub, so these may just be part outs or never built as they upgraded after their next production run cuz lyft ones were better.
I dont see any jump bikes anymore
Im still on the fence on these. I want to build with them but id rather get a bigger hub motor so i can pedal even less. Lol
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I think Jump went belly-up so the hubs and cells have hit the market.
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In case anyone doesn’t know how to read like me. This is actually just two front hub motors, and the back hubs are just internally geared rear hubs. At first I thought all 4 wheels were hub motors.
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Baaaaah ima buy one eff-it.
Hopefully they sell 1k so we all get 80 cells for free. Someone email them and tell them to bump it up to 81 cells so we can do 9s9p packs
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Oh snap, look what you miss while you’re inside during quarantine… haha.
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Just to clarify, since ebikes are really stupid with how they list their voltages, 36v in ebike terms is 10S, not 9S.
My buddy and I have been getting into the ebike world and they list their pack voltages off the nominal voltage, rather than the charge voltage like in esk8. So 10*3.6v=36v nominal.
Excepttttt they are not AT ALL consistent. For example, 14S is often listed as a “52v battery” when it is 50.4v nominal and 58.8v charged. So no where near close. And there are lots of other examples too. The whole ebike battery market is such a mess, so its confusing and difficult to tell the actual specs of what you are buying/building.
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I was gonna run 13S
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edit: never mind, seems UBER bought them out… I did read an article a while back that they were going to try and take over the world…
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