I imagine something like a pressure killswitch in the handle could possibly prevent this? 
I plan to heatshrink another of these to the brake lever to act as ADC2 regen brake. I think it should do the trick to stop this issue too.
I really like that, I will think on how I can implement it
Torque sensing is something I really wanted to try, on the friction drive I think there isn’t much sense since the torque is really low, it wouldn’t scale well, but there is chance that this project will turn into a dual 6355 motors and a 3 stage reduction to actually get closer to a motorcycle, then it would make sense
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Just printed the first half of the enclosure to see how it looks on the bike, once I have some free time I will finish the design
The surface is rough because my filament sat a long time unused and collect a lot of moisture, the nice think is that I printed it with a 0.6 mm nozzle and 0.48 mm layer height, only 2 hours and 50 minutes to print, and currently I’m limited to 9 mm³/s, maybe I can go higher than that
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Been playing around with the idea of using two 6355 motors in a mid drive configuration, should work
Flat ground at full throttle:
Flat ground @30 km/h, lots of range with a 10S13P of Samsung 35E:
28% grade @full throttle, maximum grade it can climb without going bellow 20 km/h. It should be capable of doing 30%, but at walking speeds, this is with 52 A battery current and 60 A motor
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Design done, ended with 44 magnets, probably wont need to put all of them
Third picture is what stays on the bike when the electronics are removed, the mount holds to the water bottle holes
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Awesome looking design, super sleek!
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Thanks @Lobbie
Printed the other half, and as always I’m surprised of how compact everything is, it’s hard to get a sense of size on the CAD
I was out of bananas, so hand for scale. It’s mildly warped
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Laser cut parts are done, I’ve never found a service that actually send the number of pieces you requested, at least I have a spare for all but the main rail
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I love this build.
How has it developed since?
I plan to do a similar setup but use a 2 stage reduction instead of friction.
Idea would be to use a normal outrunner with VESC and a throttle.
Have a first reduction with 15mm wide belt from 15T to 60T and then another reduction with a bike chain from 11T to 44T to the crank with a freewheel.
Thus I would have a reduction of 1:16 which should be good for a 150-200KV motor on 12s as a mid drive.
However I couldn’t find any builds like this neither here nor on ES.
My main concern is to find a reasonable way to buy/make the motor/reduction mounts.
Have you thought if this or seen any builds like it?
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I haven’t changed much, the near term goal is to finish the battery case to have it functional so I can use it to commute
The truth is that I gave up ESK8 to day to day use
What I will do is similar to you, dual 6355, but I’m uncertain on how to do the reduction, I wanted to do single stage, but having the belt close to the wheel in the mud will not be good, so I will probably go dual stage, belt on the first and chain on the second
The mounts will be all laser cut since it’s dirt cheap, and probably some secondary 3D printed parts
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Sounds like we have the exact same plan then.
Why two 6355 over one 6380?
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Just using what I already have on hand from the shelved direct drive build
But I guess for my use a single 6355 wouldn’t be enough. I’m gauging from my board that also runs dual 6355, and they already get hot on the hills around here
But hey, nothing prevents me from going dual 6380 on the future if needed, but the FSESC 4.20 may need to be replaced to use the full potential
What really is screwing me over is the brake rotor, to mount a chainring on the left side will require a fairly complex design, the way to avoid that is to go three stage reduction with the final one being chain 9:26, the 26 teeth can fit side by side with the disc without colliding with the calipers
You think that it is easier to add a sprocket to the disc side of the wheel rather than using the normal crank/derailer system?
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Esk8 parts work pretty well on low power bikes.
This is my super 73 which has a 13s16p with 30qs battery pack, single focbox and stock motor. Acceleration is okay but it rockets when you pedal. I can get it to around 33 mph and I weight 230lbs
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It seems like it has a geared hub motor with 1000W?
Yeah, I don’t want to mess with the shifters and all that, I could do the motor driving the pedal axle, but them or I have to pedal all the time or a freewheeling crank set is needed
And also I would like to have regen, if it’s like the boards we can get 10% additional range from it, maybe more since I have way more trust in a bike that has mechanical brakes in a steep hill that I would avoid eskating
I find these bikes super cool, what range do you get on them? But I would say that we can also do a high power using esk8 components like I plan, on endless sphere you find some using a single Astro motors that logs at the 10’s of kW
I don’t think it is worth it.
If you loose gearing, you have to compensate with amps to get the same torque, and thus you loose efficiency, likely more than 10%.
I think it only makes sense to drive it directly if you plan to put more power onto the wheel than a bike chain can handle.
A freewheel is the simpler option for < 5kW IMO
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Maybe, I will certainly do a bunch of tests, but it can be really efficient, just look at our boards with no variable gearing
But the bottom line is that for my bike is way more work to drive the crank than a separated chain ring somewhere
I don’t think it’s geared but I can’t be sure unless I open it.
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