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Changing to 80mm motors

Okay so the time is here, 63mm motors doesn’t really give me that crazy adrenaline rush anymore. It’s time to upgrade…

I currently run 2x 6374 192kv sk8 motors on a 12s5p 30Q battery and a gear ratio of 1:6. theese are my settings per Focbox/motor

max motor amps: 100 max battery amps: 50

The plan is to use 80mm motors on etoxx gear drive 1:5. I’m mostly considering the APS 8072 165kv motor that will give me about the same top speed as my current setup but hopefully a significant improvement to torque.

My concern is that theese 8072 motors has a rated max amp of 95A, the APS 8085 170kv has a rated max amp of 150. seems strange to me that the difference should be that big for a slightly bigger motor.

So how big of a torque improvement can i actually expect by changing out my current setup to theese 8072mm motors? I am also upgrading to a focbox unity and a 12s7p battery so i can increase the systems abillity to provide more amps but for this i want to focus on the 6374 motors vs the 8072 motors. I am aware of the fact that the bigger motor has more copper and therefore has lower losses of power. Anyone that has experience of theese motors and could provide a good answer maybe? :slight_smile:


You should stay away from the aps 8072, I’ve heard bad things about them making funky noises

Maybe just try a different brand


well i’ve seen that and the opinions seems to be mixed. I would consider different options but can’t really find any decent. the leopards doesn’t have sensors which is a huge turn off for me. maybe the APS 8085 is better but i would also have to get a shaft rework in that case, also i like the look of the 8072. the choices seems to be very limited on the 80mm motors

I mean there’s always maytech, but that’s import fees 🤷🤷

They do have a 8085, just checked…

hmm really? I can’t find any 80mm motors on maytechs webpage?

EDIT: oh okay i found it, but it’s 330$ :sweat_smile:

Oh shit haha I didn’t see the price, my bad :slight_smile:

Good luck!

what about 4wd with 4x 6374’s. lol

Well i like the idea of popping wheelies and motors in front wont really help with that… xD

Also i ride alot in the forest and im conserned that motors in the front will get smashed by stones and logs

A low kv is more important then a massive motor for large torque wheelie style, after 4000W the FocBox is the limiter

well that depends on the gear ratio, on my current 1:6 gear ratio i get simular amount of torque as a 6374 130kv motor on 1:4. having a lower top speed is not an option for me so the only choice seems to be upgrading to 80mm motors. i also max out att 200 motor amps from a standstill so i cant really get any more torque out of theese motors at low speed from what i understand

I am just saying, Torque is equall to the current x Kt, the Kt can be drived from the Kv, The only values that will change your torque on motor output with a limit to amp output is the KV, size only allows larger continuous current draw and is listed as max Watts, 6000W is a waste of money and weight

Leopard 8072 plus encoder. Seems the best way so far. Maybe the 8085 from maytech would be an option for you too. @hyperIon1 can help you there. They sensored and sealed and unsealed available. If i‘m not wrong 160kV too.

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But cheaper you can’t really get something good. The leopards are in similar price category.

I got two 8085 from aps. Still couldn’t even try them because one motor was broke from arrival.

im aware that i wont reach 6000W, my current 4500W motors doesnt even reach half of their abillity.

bigger motors has more copper = less loss of power due to lower temperature right?

also i’m pretty sure with 80mm motors i could get more motor amps at low speed to increase the torque, there has to be a reason why some crazy people are using the 80mm motors?

from what i understand this price is for a single motor? 330$


Just don’t ignore that if you are pushing the motors really hard, for the same current, the lower Kv will heat up more

Speak with @hyperIon1 if you really interested. Can’t promise you anything, but he might get a good quote for you.

But one side note. A 7p 30q gives you also only 70a batt max. That you can run with a 6384 too.

yes the 6384 might potentially reach that but at low speed the bigger motors should be able to reach higher motor amps to increase speed faster? i might be dead wrong about this but from what i’ve learned motor amps and battery amps arent the same thing

Correct! You might not be pushing your motors to the max at high speed, but when starting up from zero bigger motors (that can handle more amps or lower KV) will improve your torque. Just check to be sure that your ESC can drive the motors at whatever current you’re aiming for :slight_smile:

You right with it. But if you run 70a bat and 70a Motor Max you will get a different acceleration than with bat max at 50a and motor max 70a