Flipsky 4.20 help

Hey everyone. I recently finished my first esk8 build. I chose a flipsky 4.20 plus vesc, running dual flispky 6374 190kv motors, a vx2 remote, and a 48v 10ah battery pack. I was expecting roughly 10 miles of range out of the battery but after a few test rides I’ve noticed that it will get sluggish after just 10 minutes of riding or about 1 mile. I noticed the vesc seemed kind of hot and after letting it sit and cool for a few minutes it goes back to having a good bit of power. It seems I am overusing my battery too quickly, because it isn’t as though it is dead, just overdrawn.I suspect I have either a vesc programming error or a problem with my battery. Is there any values I can change on the vesc to help? Thanks ahead of time!

Your battery current is likely too high. Probably on the ridiculously bad “99A” default that VESC uses. Lower it to 15A per motor. You can leave the motor current much higher than that.

When you say “15a per motor” that would mean set it to 30a since I have 2 motors, correct? It only has 1 input labeled battery current max.

Nope, type in 15 but do it twice, once per ESC. Do you know how to edit the values on each ESC? Are you using CANBUS to link them?

I’m honestly not sure. I have the 4.20 esc that has the 2 linked together. How do I edit each individual one?

Bottom left in VESC Tool. (Assuming you’re using a computer and not a phone.)

I had no idea I had to edit the values on both of those. I set them both to 15a and went for a test ride. It still had good piwer when set to high but I still ran into the same issue. After a few minutes of riding it started to get sluggish. I think it may be a heat issue because the enclosure for the esc was pretty warm. I think I might try to install a little battery powered fan or something. I think my battery may be a bit undersized but it still seems to have charge after I let the board cool. Am I pushing my motors too hard? What amps should I run my motors at?

Upload a screenshot of all your current settings for both ESCs. Might have to use imgur

What battery is it?

Sounds very unlikely right now.

https://imgur.com/a/7eGntid This is the settings I have for both motors. As for the battery, I’m not 100% sure of it’s make up. Here is the picture of it: https://imgur.com/6WRPDP3

Yes that is a lot more clear.

It’s almost certainly the battery. That’s might not be a high-drain battery and probably is not good for high-vibration or high-drain use. Was it labeled for esk8 use? Esk8 need very robust (physically) and high drain (electrically) batteries.

It was sold as an ebike battery I think it said it supported like 25a draw. I plan on upgrading but I think this battery will have to do for now. Is there anything I can do to negate the effects? Would a cooling fan help? The battery hasn’t been getting hot at all and it still has good charge if you let it sit for a little while after it gets sluggish.

Then set the max at 11A and 11A is my suggestion

Ok I set them both to 10a just to be on the safe side and I’m about to go for a test ride. I’ll update after. Also I’m thinking about hooking up a small fan on my enclosure to cylce some air. How should I go about connecting it to power? I’d like it to have it’s own switch so it doesn’t have to run all the time. Is there a port on the vesc I could use to do this?

Terrible idea. Letting air in = letting water in. Water kills electronics.

But either way, the problem is likely an inadequate battery, and a fan probably won’t help that.

I took it for a test ride and it still had decent power. Still ran into the same issue where it started to get sluggish. What would you recommend for a good cheap 12s battery? Preferably under 400

good AND cheap?

Something is wrong with your setup. I use a dual VESC 4.2 for one of my boards and my setup (for hubmotors on that board) is 40A for each motor and 20A battery max (40A in battery max total) because the battery can not deliver more power then that.

Anyhow, ut runs cool with those settings, no problems.

Have you set up correct low-voltage settings on your VESC? It will reduce power output when the set limits are reached, so if this is set to high for your battery, you will get reduced power quickly.

Lets say if you have a 10S battery pack of 36 volts made out of cells that have a voltage range of 2,5-4,2V per cell (3,6v nominal). Then the highest voltage when the pack is charged is 42 volts and if totally drained its at 25 volts (its not recommended to totally drain a battery pack) Then it might be a good to set the first low voltage limit (when the VESC starts to reduce power) to maybe 32 volts and the absolute lower limit (when VESC cut of power) to 28-30 volts. Some people like to be able to drain their batteries more in an emergency situation and some want to set their limits higher to not be able to drain the battery so far down.

Anyway if these limits are set to high, lets say if the first "soft"limit is wrongly set to 38v you will run into this limit very early…


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