Well the range is based off of what was placed into the range section, which shows a 32ah battery lol
Thats awesome, thanks for the work :))
We are only one step away from calculating acceleration. F=m*a, so acceleration = force / weight (board + rider), in m/s^2. 9.8m/s^2 is 1g (gravitational acceleration). It would be interesting to see who can pull the most g acceleration. This can also be used for some extra calculations like theoretical zero to whatever speed timings.
My mountainboard for example is currently 525N, me+the board is 95kg, so the acceleration is 5.52m/s^2. My motor amps are set the same as my battery amps, which means that my acceleration is not going to drop off if I reach a higher speed. If the battery amps are lower then I am not sure if it’s possible to calculate everything accurately in a single cell.
With that and a theoretical top speed somewhere around 15 m/s (54km/h) I should be able to reach my top speed in t=v/a=15/5.5=2.7 seconds, not accounting for wind resistance (to account for wind resistance which is scaling cubically with speed, I need more than a single cell to do it accurately). But from my experience it takes somewhere around 1200w to keep this speed, which compared to my max power of 7.5kW isn’t that much so probably 2.8-2.9 seconds is reasonable. We could also make theoretical 0-20mph 0-30mph 0-40mph calculations and add it to the leaderboard.
If this sounds interesting I can add it later to the google sheet, it’ll be a few days until I can get to it though so feel free to add it if you feel like
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Yes i have a 32ah battery but it’s for 4wd so i guess i should have entered maybe 20 for rear and 12 for front or something like that.
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Yes, very.
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Hm yeah maybe that would be more accurate.
It does sound quite interesting albeit hard to predict with how many variables there are
If you add this, please add it to the far right side of the sheet, to the right of range.
I purposely left out acceleration because it’s not a metric that makes a lot of sense to compare board to board. I’d like to keep the body of the calculations focused on the 2 most important units (speed and force).
It could be interesting to see, or use in some other way, but it ultimately depends on mass of the rider, and that is not something many of us have any control over.
If it will motivate someone to lose weight, maybe it’s a good metric to report. 
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I’m currently fixing a board that would be in the running for this. All I’ll use it for is a 2 mile each way commute. It’s 7s1p with a single hub motor. Originally I thought the battery was the only problem because a cell died, but the lingyi ESC was spazzing out and hobbyking had turnigy vesc compatibles for $40 so now I’m stuck with the 7s1p battery I already built because the lingyi was 7s only. The one upside is I think maybe I can take it on a plane since it’s right at about 100 Wh. Idk how they feel about DIY stuff, but it will look pretty stock and it was a crappy prebuilt.
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Holy shit that is an old Ling Yi if it can only run at 7s. If you feel like it, then post some photos on the photo thread and link it in a reply so I can see it.
I think legally so long as you are within the battery requirements, then they can’t prevent you from bringing it with you. They may still stop you and take longer to inspect it though if it doesn’t look super well made. But also I’m not a tsa agent and they can just decide to take stuff away even if their rules allow it.
They took my tiny sheers meant for wool (felting wool) even though I made sure to ensure the rules allow it. They were cheap and not worth the hassle of getting my checked luggage back, but still sucked to have them toss them just because they didn’t want to listen to me or double check their rules.
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That’s awesome. Motor amps are set to 110
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Is the crossover from where you’re limited by motor current to where you’re limited by battery current just RPM = (Battery Amps) * (Battery Voltage)*(Motor KV) / (Motor Amps)? Naively that is what I would expect, but there could be something I’m not thinking of. It could be interesting to add a thing for what speed you become battery limited at.
Edit: Woops, fixed the equation because I had it messed up.
Maybe I’ll add a picture in a bit, but it’s in a junk pile somewhere now. I don’t know that much about lingyi stuff so I thought maybe it was just a cheepo that was made for low end boards. I also could have missed where to switch it, but I didn’t see anything to bridge for different battery configurations like I’ve seen in picture of other lingyis.
I apologise if this is a noob question but… how do you calculate motor amps and battery amps? I take it the motor amps are the max theoretical you’ll run your motors at below their rated current? Not sure about battery though…
They’re ESC settings if you have a VESC-based ESC. Otherwise, they’re hidden values that you’d have to get from the manufacturer or through testing.
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Guess I’ve got to wait until I get my ESC then haha
Well, you can get an idea of what is reasonable to use if you know the battery, esc, and motor you’ll be using. Any of the three can be a bottleneck for basically either. Technically you can set the motor amps extremely high and the battery amps low if your battery can’t handle much current and your motor and ESC can, but you’ll end up in a situation where you’re battery amps limited most of the time.
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I would run the 173kv, but I also don’t ride above 35mph.
On the 205kv, you’re going to have noticeably bad takeoff force with your current setup. It’s less powerful than my dremelseed and I can launch that thing with full throttle with no fuss.
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My take off is good and not out of control with the 173kv, but I feel like it could be just a tad more aggressive. Can I get more torque in the vesc settings or would gearing be the route you’d go!!
After looking into it more I was right earlier, but it’s a lot easier to just do Max Torque Speed Limit = (Battery Current)*(Battery Voltage)/Force. That directly gives you the speed at which you become power limited and your torque will start falling off, at least theoretically.
Edit: That gives it in meters per second, but it’s easy enough to convert.