Free Rolling + Belt / Gear Drives

I’d set my CC to 20mph as my personal preference.

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Damn :exploding_head:. How can you possibly do that :rofl::rofl:

More range. :exploding_head::joy:
I don’t feel comfortable at those speeds like beyond 50k’s. And I feel twitchy then.

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Maybe tangential but somewhat on the topic. If you (someone/anyone) were to implement brakes, it sounds like the idea is to ensure that they are manually operated otherwise whats the point right? So with normal esk8 thane this would have quite the spatial issue. Though with 8" penu’s and up this seems more like something that could be doable. The question when space is no longer a constraint is where/how is this ‘mechanical’ or ‘manual’ actuation going to take place.

I cant see that there would be much capacity to utilize a brake with your feet, and the idea that you’d need to be tethered to the board with a cable seems to be a little backwards from what most people want. The only approach that I’ve brainstormed appears to be an electrical component especially considering having the brakes embedded into the electrical control of the board would make braking more intuitive than having to throttle down - and press a completely different brake at the same time.

The only system I can assume is optimal is electrical primary actuation and a board mounted bypass if the shit hits the fan.

I am curious if anyone else has considered this idea and looked at an actuation approach that seems… in a word, Viable.

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I respectfully disagree based off of what I’ve experienced but am interested in discussion. There are no magnets around a coil in a manual bike setup to provide resistance.

  1. If I hand spin a bike wheel by itself, the loss of forces are solely on the bearings and a tiny bit to the ratcheting system.

  2. If I hand spin a motor with a the same bike wheel attached to it, the loss of forces are in the motor bearing and the constant electric field generated working against the motor magnets (internal winding resistance, why hubs roll more freely at low kvs)

@spade I’m glad you started this thread, I’ve been thinking a lot about this recently.

Specifically,

Does regen braking recoup more power than a (more or less) frictionless system?

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If you take into account rolling resistance on the road understand load there is a vastly different resistance value.

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If it’s the same wheel, it would have the same rolling resistance loss to the road in each case.

I’ve always wondered what happens to the free rolling energy at speed though. That doesn’t recharge or deplete battery so it points to your argument of minimal loss while rolling.

I have no recorded data to test this idea on, just been on my mind.

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In a powered vehicle, it rarely makes sense to decouple the motor to coast. Most energy is lost to wind resistance, and on flat ground, whatever energy is lost to wind while coasting will have to be made back up when the motor re-engages. It’s more efficient to keep the motor spinning and engaged to keep the vehicle at a steady speed.

In hilly conditions, regen braking will always be more efficient, even if marginally, than mechanical. As 100% of mechanical braking is lost to heat, part of regen braking is recovered.

In high performance requirements, i.e. offroad, steep terrain, racing, etc. Mechanical braking can/will outperform regen, which is why no car relies 100% on regen braking. But efficiency is out of question here, it is simply a matter of what works better.

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I don’t either, just personal experience. What do you mean the same wheel?

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Just imagining an esk8 motor attached to a bike wheel vs a ratcheted bike wheel on its manual hub rolling down the street.

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I feel like the only way a ratcheting mechanism will be more efficient is if your riding involves accelerating up to x speed, then coasting without touching any brakes until you slow down significantly, then repeating. Not sure why you’d ride like that but :joy:

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Switching to gear drive at the moment, but with the belt setup before I set them loose as fuck and kept adding a little tension at a time until heavy braking from full speed wouldn’t skip anymore, then add a little more for a safety margin. Dumping the throttle from 30-35mph wasn’t even close to throwing me off the board, noticeable drag but nothing more.

On the subject of mechanical brakes. I think having anything electric involved makes them completely pointless. Something like 2 brake discs in the front with a little pedal somewhere on the board it wouldn’t get in the way and would still be practical to use. Not ideal but it’s too busy in the back for any brakes.

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ive been toying with the idea to modify this concept to fit on my board, shouldnt be too difficult even without going straight thru the deck

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Isn’t dumping the throttle more affected by your throttle ramp down time? I remember setting it to 0s one time and almost ate it right in the parking lot lol

You forget the option that tiny disc brakes can be attached to the motor can instead of the wheel.

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Why does this picture exist. Why is he not wearing shoes at least. Why do I think it would be a good idea to do that with the battery enclosure…

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I like to come off as very drunk and irrational while riding :sweat_smile:

In my mind I’ve always imagined the motors providing more resistance at free roll.

Why would dumping throttle throw you off without significant resistance then?

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That’s true. I just use whatever the VESC default is. :sweat_smile:

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pogo brakes

sorry it was the first pic i found :innocent:

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There’s definitely more resistance with the motors while free rolling. But when averaged against overall efficiency, there is no gain to decouple the motors for coasting…

Throws you off because you lean forward ahead of the board to counter the acceleration, and when you dump the throttle when no ramp down, acceleration stops instantly and you don’t react fast enough to center your weight back over the board

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Thanks for the explanation and to @mmaner as well.

I wonder if the metr or other telemetry devices keep a running total of Ah recouped via braking I could use as a reference :thinking:

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