Speed needs battery amps, torque needs motor amps
But you shouldn’t overset the motor amps unless you turn down the battery amps
Those also weren’t the numbers I suggested
Ahh yeah I forgot you suggested numbers, lemme find those and use them.
Correct.
Where I’m going was, to get to speed you don’t need a lot. At least not more than you need for high torque.
If you want to ride fast very quickly, then you need more amps.
So here’s where I am now. I find with the mechanicals on my board I need about 45A for most hills (from metr logs), so I went 50A to be safe.
metr was reporting ~18Wh/Km to ~21Wh/Km average across rides.
Can you remove the shield of a zz bearing?
They were super rusty and crusty with some sort of grease, so I brushed them down, washed them in hot soapy water, soaked them in gasoline, spun them up to 15k RPM, and added a couple drop of speed cream…better but not great so I want to open them up and get at the balls inside (air blast out the gunk and get the speed cream all the way in)
Maybe half the speed cream made it, most of it pools up on the shield
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not sure how u would reuse the metal shield tho
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Hmm, I think I’ll run them for a while like they are now and if I have issues I’ll destroy a shield on each, I guess the open side stays in the hub so hopefully not too much crap gets in
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i don’t know if its possible to get some plastic shield to replace those metal one, but worth a try?
I don’t have any donor 608 sealed bearings on hand, all shielded or in use
Can someone help me figure out ERPM limits in vesc tool? I’m trying to setup a ppm remote for the first time and I want to limit the speed that the board can go backwards. Right now I’m using current hyst reverse and whenever I push back on the remote it basically goes full speed. I tried to limit the negative erpm in motor settings but then it will only spin up to ~30% duty cycle when going forward.
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Did the motor spin in the direction you wanted it to after running the motor wizard, or did you have to click invert direction? That might be causing it?
I did have to invert direction of one of the motors, how would that be affecting the rpm limits?
limiting erpm would result in losing braking ability once motor spin exceed that speed, i do not recommend that
Erpm limit is 60k for 4.xx hardware and 100k for 6.xx+ hardware
They will freewheel much faster because there is no load, 3 amps at no load is enough to hold max speed
Low battery amps, high motor amps = more torque
Low motor amps, high battery amps = more speed
What happens at higher Voltage, unchanged amps?
How about unchanged voltage and higher amps?
higher top speed
unchanged top speed, but u get to top speed super fast
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Isn’t the limit for 6+ 150k? From the VESC manual:
Depending on the Hardware you use, it may be limited to 60000 ERPM (e.g. HW rev. 4.xx) and you should pick a motor not reaching this limit.
Going beyond this limit may damage your Hardware! The VESC SIX design can reach up to 150000 ERPM.
If limiting the ERPM causes a loss of braking ability above that speed, why does metr use ERPM to regulate the top speed? Isn’t that dangerous?
What’s actually going on there?
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esc can’t drive a motor over the erpm limit, but gravity (or other non esc driven propulsion method) can, and that’s how u lose ebrakes
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I think I may be misunderstanding how the ERPM limits work then. I thought you used those to limit the speeds that the board can go, but from what you are saying it seems that they are more for limiting the RPM that the ESC can push so that the hardware doesn’t break. In order to limit speeds would you limit duty cycle then?
Also please let me know if my understanding is off here.
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