# Need help solving a math problem regarding range and battery consumption

Hello everyone,

I’m currently working with @okp to change my Bamboo GT battery, but I still have the old one, and as you might guess, it’s not what it used to be. So I have to use it on my daily commutes and I can barely make it (10+km). One thing i’ve noticed is that it’s about the same or better if I do some pretty big accelerations in fast mode and glide a bit, than using eco with the finger on the throttle pretty often (not even fully pressed). It’s obviously faster and make my commute shorter too.

What I wanted to know (and it might be very confused since that’s the way it is in my head) is if there’s a way to calculate or have an idea about how all of this works.

For example, if I’m on flat ground an regularly pull 20A off the board to keep a steady speed in ECO, i’ll go pretty slow, and my commute will end up being longer, so i’ll have to pull those 20A longer and I won’t glide much. So i’ll pretty much use a lot of battery.

But if I press Fast pretty hard and launch myself at 30kph while momentarily drawing around 50A which is more, but , i’ll go way faster and be able too glide longer, my commute will be shorter.

All of this seems really counter intuitive, but something tells me that it actually make sense.

So my question is : Does having a more agressive riding style actually make you save some battery ? Also on a side note, does wheel size matter ? Are motor more efficient at certain speeds (I knwo they are but what’s the ball park on a setup like the BGT? Like the bigger the wheels the harder they are to drive for the motor, but also to stop, so the board might glide longer (and go faster too since the wheel is bigger).

I know that you normaly have to use the same amount of energy to go from point A to B if you use the same vehicle and path, but there’s a lot of variables like motor efficiency at certain speeds, the time factor which is dependant on the speed, and also the unpowered (electrically) glide.

Sorry if it’s confused, but i’m sure someone actually made theories about all that here

I’d assume by having a more aggressive riding stance, one lower’s their moment of inertia and accelerates easier, requiring less of the battery.

No; the opposite actually.

Yes, typically at higher rpm the BLDC motors are more efficient

The only thing I can suggest besides getting a new battery for it is that kick-pushing to get yourself moving, then using the battery to keep moving, is way more efficient and should make your battery last a lot longer. Also, all other things equal, every battery will lose capacity over time. Some faster than others. This won’t get better by itself – in fact, it will get worse.

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I know it sounds counter intuitive since I squeeze out more juice in a shorter timeframe but I also glide more and my commute is shorter since i’m going faster, the reason i’m wondering about that is so I can find a sweet spot to ride my shitty battery deck. I already kick push when I can so I don’t fuck it up even more with the power spike of a 0kph start.