I want full control over my vehicle — a vehicle deciding to engage a brake on its own because of a measurement (besides human interface device) sounds like a new way to die.
But yes, the battery full problem is very, very real for me as well.
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This is exactly why I’ll never buy a OneWheel or EUC. Perfectly illustrated.
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Well, I mean… It’s not like you DIRECTLY control braking via EBS either. Also, I am talking about the rear wheel. Even in that locks up, it’s far from a death sentence. Front wheels locking up - I am 100% with you lol.
The thing is: mechanical rear wheel brakes (even without servo control) are basically non existant for esk8s.
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Because the motors are in the way 
Find a way to put the brake on the motor can.
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One could have a disc brake attached to the wheel pulley.
This would work better on AT boards.
Have the pads for the disc attached to the motor mount.
Custom motor mount would be needed.
Seems like it would fit better attached to the propeller mounts — these four threaded holes that are on the front of many models of motor cans:
Wheel pulleys are already large and adding something larger to them is not ideal. Motor pulley would be a better option. Or a strap drum brake around the can.
This got me thinking, what about brakes that pinch the belt? Would only work on belt drives but it’s an idea. The mechanism could exist on the mount between the motor and wheel pulleys.
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You could literally just step on a button going through the deck that pulls on a stainless strap wrapped around the motor can.
I think that would destroy your belt in short order. Rubber is a lot less durable than cast iron brake rotors.
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use the motor can as a brake rotor?
Yes.
A friend of mine is building an mtb based on meepo stuff, gears 15/75 wheel 20cm,
The remote has a small display but I can’t get it to display a realistic speed: there’s only one setting and I don’t get what it’s supposed to be set to :
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If you turn the number down, does the displayed vehicle speed get closer to, or further away from, the correct speed?
no one does 
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Anyone know the difference between the Stormcore 60D and the 60D+
I see the 60D+ is on backorder & only $20usd more than the Unity.
My Flipsky Flipshitted & looking to upgrade.
When at 99 it’s much higher and at 10 (which is minimum) much slower, I guess I could try until I get a good approximation but I don’t have an accurate way to measure the boad speed
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Ride the board and measure the speed with gps, change the remote until it fits the measured top speed.
Probably the most accurate you’ll get.
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I have a question about voltage sag… people say increase p-value of your pack = less voltage sag. I imagine that is purely because AH of the pack are increased… am i right?
I am asking because I am considering doing a Lifepo4 pack with Headway cells (https://www.evcomponents.com/headway-40152s-15ah-lifepo4-cell.html).
only 12s1p but a 15 AH pack and rec. constant discharge goes up to 75 Amps. I know others have used these cells or at least talked about them as a viable option. It would be a very cheap but heavy pack I would use for a dual motor longboard with 110mm street wheels. I figure with 15AH I wouldn’t even stress the battery or test it’s sag until mile 10 or so. Even though its a 1p. I currently have a 14s2p lifepo4 a123 cells and while theyre great… I find myself not going full throttle on some hills to be gentle to pack/ trigger low voltage. just looking for something completely bulletproof that I could abuse if i wanted to
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I think some people use voltage sag to describe two slightly different phenomena.
The main one in my mind is “draw more current from the battery and the voltage dips”. This is because there are actual resistances in the pack (weld points, solder joins, wires) that obey ohm’s law, so when you run a current through a resistor there is a voltage drop developed across it. There are also parts of the chemical reaction in the batteries that act sort of like resistance, so you can pretend they’re a resistive element. Same thing applies, current through a “resistor” drops voltage. The reason that adding P groups helps you with this is because adding parallel paths for the current reduces resistance. Think water in pipes, if you add more pipes alongside your existing one you can push more water through without having to add crazy pressure.
The other version that I sometimes see (and don’t really like calling sag but I could be wrong) is related to this:
That’s not the battery responding to a high current draw and the voltage dipping under the load, it’s just the battery going dead. This would be helped by having bigger capacity, because the battery doesn’t go dead as quickly. The voltage produced by a pack reduces depending on how much charge is left in it.
Small bit of extra nuance is that LiFePO4 has some different characteristics to Li Ion. Specifically, it doesn’t change in output voltage as much depending on its state of charge. If you’re comfortable reading the graphs this shows as a flatter discharge curve, basically just that the change of voltage with respect to capacity is more flat (for the majority of its discharge, there’s a spike near fully charged but just don’t charge to 100% and that goes away).
Lithium Ion - you can see the slopes are a bit steeper, meaning they lose voltage relatively quickly with regard to charge level
LiFePO4 - a bit flatter
If you want a really quick and dirty way of reading the graphs, mentally change the labels on the axes to “Miles ridden” on the bottom, and “available speed and power” on the vertical. That lets you plot how much power is available at different points on your ride.
TLDR; P groups help you from reduced power at high battery draw (+ also adding capacity), just adding capacity by itself helps you avoid the feeling of limping home with no power left on a nearly dead battery because you just don’t hit a nearly dead battery as often
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What’s your VESC voltage cut off settings? 14s2p of those A123 should get you like 140 battery amps, so maybe it’s the pack construction or too high of a voltage cut-off that’s limiting performance?
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