Changing to 80mm motors

Battery max current will limit battery max wattage; acceleration should be the same, but at 50A battery max it (acceleration) will start to decrease at a lower speed than at the 70A max. (From what I understand)

you will get the same acceleration up to 71% of your top speed at the current battery voltage

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going for 12s, maybe even 13s if the focbox unity are proven safe to work with 13s, anyways it should be enough to drive the motors

That’s right! At low speed it will not change

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and this is why im interested in bigger motors since i want that crazy acceleration from a standstill

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I don’t understand what is wrong :sweat_smile: Don’t want to say, don’t go with 80mm motors. By no means it’s for sure fun, as min I hope so with mine :stuck_out_tongue_winking_eye: But honestly my dual 6384 170kV and 1:4.7 gearing let me make crazy wheelies when pushing the throttle full from stand still and even from like 5km/h With a 1:6 gearing the acceleration should be pretty pretty good already. :sweat_smile:

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yeah it has great acceleration already, i guess i just got used to it and i want to be scared when i pull full throttle, when i first finnished my build i got some serious adrenaline pumping from this setup and i want that feeling to come back haha. Also i’m quite a heavy guy at 95 kg so i guess that affects the acceleration aswell.

i clocked the acceleration. it goes from 3-4 kph (just rolling slowly) to 40 kph in just over 2 seconds

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I want to pimp my Bajaboard with 4 big 80xx im interested to see how you get on with whatever you try :smile:

I’m thinking 13s5p for front and same for rear (using focboxes)

hahaha but already having 4wd you feel like you need more acceleration? xD

So if you use the unity with a max not continuous current supply of 300a that means your battery has to be able to supply 212.13amps, each motor would be seeing 5100watts for a brief time during hard acceleration, the continuous current is 80-100 motor amps making the maximum continuous current draw from battery 142 amps and at 12s a motor that is ratted for 3500W is a maxed out due to the limitation of the esc

I have both a 170kv 6374 max 3400Watts and a 6484 170kv max 4000Watts and they both draw the same current and have the same torque, the 6384 just can outlast the other if esc limitation isn’t a factor

You running 100 motor amps right now, right? I would have atleast tried to increase this first, before buying new motors. As far as I understood you havnt had any overheating issues with either the focboxes or motors? This means that you havnt pushed either of them to their limits with your current settings. Try increasing your motor amps to 120, you’ll be suprised how big of a difference it makes :smile:

This obviously only apply if you havnt had any overheating issues.

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I’m not sure if the 300A Unity rating is for the battery input or the motors. In any case, even the TorqueBoards ESC boasts that it can do up to 240A for a single motor for a few seconds, so I think the Unity can safely do more. Do keep in mind that we’re talking about startup acceleration, so the motors won’t be running at max voltage, and therefore the power draw will be far less than what you state. I’m actually quite confused as to how you calculated all the numbers you mentioned; seem to appear out of thin air :smiley:

youre assuming this is right… The vesc might be able to do 240a, but how long is a few seconds? 2? 3? How long does it take for your amp load to lower because youve reached speed?

seems like a very misleading point, as ive thermal throttled with less than 5 mins of riding time, 30a each, two big hills(no crazy angles or “impossible” hill degrees)

no shot any 4.xx can take 240a for a few seconds… except maybe chakas? Thats alot to ask for 4.xx HW

@rusins ive edited it so it reflects my complete thoughts. sorry. I have a bad habit of submitting the comment and then editing like my life depends on it for the next few minutes

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It does sound a bit unrealistic tbf :thinking: :smiley:

Edit: @Sn4Pz you and me both, bud! :smiley:

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https://www.hyperionesk8.com/collections/brushless-motors/products/mto8085-160-ha-c-e-skateboard-motor

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https://www.hyperionesk8.com/collections/esc-vesc-contollers/products/mtsesc6-6-200a-esc-brushless-motor-controller

For the water sporter… https://www.hyperionesk8.com/collections/esc-vesc-contollers/products/mtsf300a-opto
https://www.hyperionesk8.com/collections/brushless-motors/products/mto8085-160-g-brushless-motor-for-hydrofoil-electricc-suf-boards

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Motor amps values are not the same as battery amp values, if you run your motors with a multi meter connected, you would see the voltage the motors run is a lot less then power source, I have an Exel calculation sheat that graphs the voltage conversion and expected amp draw from power source. That’s how I pulled the numbers

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That is correct, 100A is the manufacturer rated limit. I never even got close to overheating, one thing to consider is that i finnished my board in novemeber and have only been riding in temperatures between 5°C to -15°C. When summer comes it might be another story