vesc field weakening

Who here doesn’t want to go a bit faster lol

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Most here hold reliability in high regard.
Field weakening is still too mysterious/risky

The onewheel guys who do vesc conversions run field weakening and don’t seem to have any issues with it.

I’ve run it quite a bit too

Functionally the biggest drawback is heat and less range. If you are locked into a hub motor it can make sense, otherwise you are better off changing gear ratios, tire sizes, kv or battery voltage to get additional top speed.

One thing to consider is that if the vesc faults or loses power while in field weakening, the voltage at the motor goes back to RPM/kv which may exceed the mosfet rating. Probably best to use a 20s esc for 12s for example, or use erpm limits to make sure it cannot exceed the 60v mosfets most 12s controllers have


Not a single mention in this thread or the older one on the same topic, on any hardware requirements for Field weakening.

One could assume that a vesc 6 with 3 phase shunts would be safer running FW than like a Focbox 1.7 but no guidelines seem to be around.

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I went from 72t to 66t and didn’t gain any top speed at all, any idea why that happened? I thought it would pick it a bit of top speed, not much but none at all?

How are you measuring your speed?

GPS app on my phone. I was doing it with my remote at first but I couldn’t belive I was going the same top speed with the 66t as before with the 72t so I downloaded the GPS app on my phone and that confirmed that the speedometer on the remote is pretty accurate.

What speed do u get to? Maybe you need to increase ur battery amps to overcome the increased wind resistance

Probably not enough torque to go that speed, need more amps, like @hummieee said