Bottleneck Factor of Hard Acceleration?

In terms of hard acceleration from a stop (drag race scenario), what is likely to be the limiting factor prior to top speed that would cause you to overpower the board and nosedive? Duty Cycle? Current? Something more ambiguous? This is assuming an aggressive tuning that will make sure to keep the nose off the ground if the power is there. Maybe @badgerwheel has some input after having to tackle this issue with BadgerSense?

Just trying to get some insight before I try pushing the limits a bit more for some quick drag races vs. GT, so I know a bit more of what to expect. I haven’t had the guts to push it to the limit on a drag race scenario yet (gotta pad up for the confidence lol), all I know is I’m only hitting 50% duty cycle and 20A current and definitely accelerating more than a GT already lol.

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Side question as well, I’m basically pushing it as low as it can go with Max’s tune without getting too sketchy for nose clearance, so might have to make it more aggressive to really show the potential if you tune it for the job. Any thoughts on what makes the most sense for making the board more aggressive in a drag race start? I know both dropping Mahoney KP and raising P have this sort of effect, still figuring out the relationship between the two and what might be the best way to go about changing them for this scenario.

Documenting here for future reference, message from @uyle:

“Initial thoughts are current limits being hit. Both battery current as well as motor max currents. For a brief moment I would turn both those up so you don’t hit it. The main danger is thermals but in a short drag race you should be fine. Especially if you let the board rest and cool in between runs. I wouldn’t recommend it for long hauls but short bursts it should be fine. Outside of current limitations you can raise P, Yaw P and lower Mahoney KP. I would play with those three as well as the torque boost for drag race specific settings”

Motor current is what limits acceleration, at higher speeds battery current is a factor too. Given the capabilities of the LittleFOCer though the limiting factor is probably the motor, i.e. you get to a point where pushing more amps into the motor only increases heat and doesn’t increase torque

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Is there some sort of guideline I should follow if I were to start pumping up the motor current? Or would it be a bad idea to push it beyond my current settings of +/-140A? Not sure if that number is based on anything or just what people have found to work well without too much risk. For context, I’m a 105lb dude and have never gotten a board to really come close to overheating, while riding hard with plenty of other people that have overheated XR’s and GT’s haha. I’ll definitely keep an eye on thermals if I experiment more, but I’ve also got some more headroom than the average rider in that department.

my advice would be to start logging - this is the best way to learn about all the ins and outs of how the thing behaves

find out how many amps are you Actually pulling and for how long

if you see evidence that you are indeed able to keep 100+ amps for more than a second or two then you can try increasing the amps

and no, there’s no guideline

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and don’t worry about heat, no reason to - you can see live temperature data in the app, if it starts getting hot then take a break

Copy of my message from the chat:

Without FW limits, a nosedive/cut-out would be caused by HW failure (a blown component, wire, battery, connector, windings, etc). So most FW limits (BMS or controller) are around what the HW can handle (like Dado mentioned), though it can fluctuate. Eg Amp limit is good start but can be to high or low since available wattage changes with battery SoC (%), hence why some use duty cycle instead. Assuming your tune keeps the nose off the ground when pushing it, the controller will pull power until one of those FW limits is hit, or the HW fails. Good luck, and pad up."

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What temperature we talking about for “hot”?