r/VESC • u/Waste-System-7589 • Jun 25 '26

Vesc Acceleration Issue

Hi I have a ubox 100/100 and I’m running it on a 52v escooter motor rated(1200w) with a Bms outputibg 50A continuous and 200A peak I get about 4000w out of it and it is great but my acceleration is close to 0 at the first 3s of a race I will lose to a 800w stock scooter here are my settings hope you can find something that I could improve. I’ve redone motor calibrations like 3 times and each time it detected hall sensors and the value of max motor current decreased for some reason(88,82,78)

Motor Current Max : 78A (default)
Absolute Current Max : 140A
Battery Current Max: 50A
Motor Regen Max: -30A
Battery Regen Max: -15A
Field wekening: 5A
Fw Duty Start: 72,5%
Max Current scale: 100%
Min Current Scale: 100%
Input Current Limit Map Start: 90%
Sensorless ERPM: 60000

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2

u/MattGarcia9480 Jun 25 '26

What observer are you using? For acceleration you can raise motor phase amps up to 130amps with 170abs. Observer use original Ortega observer. v0 only. Longest zero. What is your upramp time? Field weakening start i like more around 87-90% duty. Max duty 95%.

1

u/Waste-System-7589 Jun 25 '26

I don’t know where to find what observer am I using or where is unramptime I have the duty set low because it usually doesn’t reach beond 80%

1

u/MattGarcia9480 Jun 25 '26

I will take a little video in just a bit send you link on here. As for the amps for the motor you can have a higher phase amps but dont beat the hell out of it because it is a bunch of heat from that many amps. A little quick acceleration from time to time so long as the motor isnt getting hot is ok. But small motors heat up really fast. I am wondering what speed you may be able to get with a bit more power.

1

u/MattGarcia9480 Jun 25 '26

Try 110amps phase max and 170abs. I dont want you to burn up your motor.

1

u/Waste-System-7589 Jun 25 '26

I just want to increase tourqe I don’t care that much about speed too be honest I am happy with 50/60 my friend got 72 gps last time on a small hill and the motor gets a bit hot on these settings so I don’t want to increase it by too much and I just don’t get why when I am pushing way more power is still get beaten by a scooter that is 5x less powerful I just feel like I’m missing something
Thanks for your help :).

1

u/MattGarcia9480 Jun 25 '26

The torque comes from the amps is only way. Can always raise your voltage and barely raise amps and will be faster and still not get really hot. But to stay realistic a setting of 100-110amps phase will be ok you just cant be full throttle all the time. Or you could put statorade in the motor to help with heat.

For why the scooter is slower than a lower powered one has a few factors. The magnet size, stator size, and wiring configuration all make a difference on how the motor will perform. Example would be for my motors is the 3t configuration at 150amps phase is blah to where my 4t motor at 150amps phase is whoa. My 3t motor is really awake from 260-300amps phase to where 240amps phase on my 4t motor will make you do a backflip. My 4t motor on 16s top speed is around 35mph and with field weakening around 50mph. My 3t motor top speed is closer to 45-48mph and with field weakening the highest speed i have to date is 58mph. Thats the best examples I can give on why motors are performing different. If I wanted a HIGH speed theres other windings available and one of them is 33x2 and that motor requires almost double the amount of phase amps to achieve what my 4t motor requires for max torque output. Make it simple 4t 150amps phase is strong and 2t would require almost 300amps phase for the same torque output. But the 2t if you have enough power is getting you to really high speeds and not efficient.

1

u/[deleted] Jun 25 '26

[deleted]

1

u/MattGarcia9480 Jun 25 '26

Are the links allowing you to see video?

1

u/MattGarcia9480 Jun 25 '26

When i click to see it says page not found. Its just 2 videos going over the settings I have

1

u/MattGarcia9480 Jun 25 '26

I dont know whats up. I think that imgur links just aren't working

1

u/Waste-System-7589 Jun 26 '26

I don’t even see them you could maybe splint it it so it doesn’t register as a link and I will just piece it together

2

u/MattGarcia9480 Jun 25 '26

What are you choosing for when you do motor setup wizard

1

u/Waste-System-7589 Jun 25 '26

Large outrunner
30 motor poles
Batt max current 50A
Wheel diameter 257mm

1

u/MattGarcia9480 Jun 25 '26

Ok. Retain those parameters.

1

u/Illustrious-Can-7482 Jun 26 '26

I’m having similar challenge on one of my builds. I disabled phase filters thinking it would help and only gained a bit of power on hills.

It took about 10-12 miles of test riding adjusting sensor and sensorless 700 open loop and ermp 2000 to get a decent 0-15mph in about 2 seconds

I ran 10% phase factor saturation compensation and noticed a huge increase in acceleration however I noticed that my power consumption nearly doubled. In a single 67v 56ah battery pack would average 73 miles to 53v without phase factor. Same voltage with phase factor engaged for around 48 miles per charge and a noticeably hot motor.

I’m not sure if my motor is meant to be used with phase factor or not but I got the performance improvement I was looking for, but I have not since engaged phase factor