Are you sure it is skipping on the wheel pulley?
Usually the skipping happens on the motor pulley due to the low teeth count engagement.
That’s like telling a motorist that to improve their fuel economy, they should switch to bicycle 
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I agree 100%. Even with big heavy dual drives, I still grab the single-motor short commuter boards about twice as often. The ones I grab more often, I build more of.
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No, its skipping in the motor pulley, but what I mean by smaller pulley is that any deflection is causes a larger diference in circumference than with a larger pulley, that and running higher current for a single drive. My other mount has place for a idler, so that will help
My plan was to test it today since its the first day of vacation, so it’s obviously it raining, after at least 6 weeks without a drop
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More tests, increased the gearing to 36/14, was only able to get the motor to 65°C, but keep in mind these weekend had the coldest day of the last few years, so not really representative
I recently built a lightweight commuter board. Single 6355 flipsky, 10s2p VTC6, 16/32T 15mm belt + idler, 83 Wheels, Focbox, Motor 45/-45, Battery 30/-10 running FOC. No over heating so far, but I have a problem with braking, even riding flat. I’ve tried different vesc settings, but it’s still the same.
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Nice
What happens on the brakes? Weak at high speed? I think your gearing and the negative currents are both too low, if you are no reaching top speed I would go 16/38 or even 15/38, and increase the braking motor current to -60 A and the negative battery to -15 A or -20 A
I’m not sure if can increase the regen to -15/-20 since vtc6 max charging is 5A so 2p would be -10. Maybe i’ll try increasing motor current 60/-60.
It won’t help if your braking problem is at medium to high speeds
The way I think is, the cell won’t explode or anything like that by having a higher current pumped for a few seconds, I rather have my battery die a bit sooner than need to brake and the brakes are too weak
Make sense, i’ll try that, i don’t care if the battery die sooner rather than no brakes when i needed 
.
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Experimenting for a future direct drive for this build, just tested it inside, torque is low but I have plenty of headroom to increase the motor current, but braking sucks
@mishrasubhransu your best result was with the current mode and a really low reverse speed right? or its the new current hysteresis?
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I like how you made a 1:1 belt drive to simulate direct drive.
Yep. not hysteresis.
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Thanks, will try that
The free roll is a lot better than with my usual reduction
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The current mode works perfectly, limited to 2 km/h in reverse
Running 40 A each motor the performance is surprisingly, and so smooth and quiet, the belt/pulleys and motor doesn’t make any noise at these low rpm, only thing you hear is the wheel
In this short ride apparently the things do heat quickly, and if you look the average motor current is 20 A, double of what I usually get
Consumption is the more or less the same at 9.45 Wh/km
Another test, this time with 60 A on the motors, performance is really good, definitely usable, braking is good enough, I may increase even more the braking current since it’s used for a short amount of time and wont heat up the motor a lot.
The only thing that lacks is low speed performance, probably because as @Gamer43 said the motor tracking is not accurate at low speeds, and since with these configuration the rpm is low for greater range of speeds you feel it more
Another issue I’ve thought it could happen and probably happened is that the active braking is not considered braking on the temperature protection logic, so if you use the temperature acceleration decrease and the motor is hot, what happens is as you transition from passive to active brakes it cuts off since its too hot. The problem is further increased due to the noise that high motor current induces in the temperature readings. @mishrasubhransu did you run in anything like this or you never get your motor that hot? not fun while you are going downhill
I have a topic about it on the VESC forum
https://www.vesc-project.com/node/997
@rpasichnyk the announce feature is really useful for tests like this, never had used it before, well done
And finally the logs, took it to some hills and climbs no problem at full speed, max motor temperature of 72 °C and consumption of 11.2 Wh/km
I will do some longer rides, increase the motor temperature limits and turn off the temperature acceleration decrease and see how hot it gets, if this turns into a direct drive for this build I will find a way to incorporate a fan to really force air through it or seal it completely and use Statorade
https://www.ebikes.ca/shop/electric-bicycle-parts/motor-hardware/cooling-mods/statorade.html
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Increase your sensorless erpm limit to some higher number. Try 10000. My motors have gotten to 75C max.
Will try that, apart from the cut it’s performing flawless, I don’t know if I really need to up it, I have less poles than your DD, maximum speed is set to 35 km/h which correspond to roughly 17k Erpm
The reason I am suggesting that is because normally you are moving the motor at much higher angular velocity but in 1:1 ratio it’s much slower.
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One more ride, now running 70 A on each motor, 79 °C max, took it at the steepest hills I have nearby and climbed it no problem without loosing speed
It’s funny that in the 1:1 with high Kv the current limits occur in the opposite way as a normal board that the motor current is reduced to keep the battery current within the limits, here the battery current climbs as you speed up and the motor stays constant. It’s expected, but nice to see
@Pedrodemio
I think I know why the VESC has poor tracking at low speeds.
So at low speeds, obviously the BEMF is very weak and small compared to sources of noise.
I realize now that in the VESC designs there is actually quite a bit of crosstalk between the current sensing section and power stage, so what is happening, is the sine waves that the VESC is applying to the motor is also showing up in the current sensing that the VESC then measures. The result is this crosstalk skews the estimated BEMF and causes the estimated BEMF to either lag or lead the actual BEMF. The strength of this crosstalk noise is proportional the to applied motor current, while the strength of the BEMF is proportional to speed.
This is explains why the tracking improves as speed increases, and also why torque appears to drop off as more current is applied, and why I can actually get my VESCs to cog at very high currents.
The solution to this is careful PCB layout and component selection to minimize and filter this crosstalk.
I recommend using current sense amplifiers such as the INA240A1, which has significantly better common mode rejection than the AD8418. Placing the amplifiers right next to or very close to the MCU will allow for the output signal from the amplifiers to be mostly unaffected by noise from the power stage. This means the current shunt kelvin connections will have to be routed through the power stage, this will cause the crosstalk to appear as a common mode signal in the differential current sense traces. Keep these traces straight and as short as possible and try to sandwich them between ground layers in order to minimize crosstalk, which the INA240’s common mode rejection will then filter out.
The INA240 costs the same amount as the AD8418, but has way better electrical characteristics. 30 dB better CMRR at DC, 20 dB better CMRR above 1kHz, much lower input offset voltage, gain error, and temperature drift.
It is also a drop-in replacement.
Why new VESC6s don’t use the INA240, or at least test with them, is beyond me.
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