Focbox Unity reaching thermal cut off

Noticed my board was throttling going fast up hill. I checked the info on Davega and it reached max mosfet heat. Motors are also getting hot. My settings might be a bit high, just trying to get the max out of it.


Would it benefit to go with bigger motors like 6384 170KV?
My setup:
Maytech 6374 170KV
Molicel p42a 12s6p
Focbox Unity
Bypassed smart BMS
3dservisas FatBoy 12t 36t
BKB 155 tires
Motor current max 88A
Motor current max brake -70A
Battery current max 42A
Battery current max regen -40A

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bigger motors will help your motor temps due to the additional thermal mass, but won’t make a difference for your ESC temps

do you have a heatsink for the ESC that’s exposed to airflow?

ive heard that people lower battery amps to get their ESC to run cooler, haven’t tried it myself tho

i was thermal throttling my ESC even in winter temps… added a heatsink and it stays cool even on hot summer days :ok_hand:

edit: just noticed the temps in your pic are in farenheit, so those numbers are nothing to worry about… is that peak temps?

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89°F is not even that hot for the esc temp

that’s, like 30°C, you can go up to like, 80-100°

your motor temps are however, pretty toasty, you can eek out more by raising the limits but it’ll probably not do much

bigger motors might work, but you’ll likely still run pretty warm, probably round 60°C if i had to take a guess

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Motor temps are causing the bottleneck here as others have said. The 1:3 ratio on 6" tires isn’t doing you any favors here, neither are the maytech motors. Easiest solution here is to pick up larger, better motors

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+1 for this being an issue.

Get more teef

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What motors would you suggest?

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Is it possible to change the teeth with the 3dservisas gear drives?

I took that picture when I blasted up a long hill and felt the board act weird.
It does have a heatsink for the Unity.
That is the hottest I’ve seen it get, it has done that weird thing a couple other times.

What trucks, transmission, and/or mounts are you using? How much space between the motors? What is your budget situation? Send pics (I see that pic above does show some of this)

We can definitely help

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your esc only reaching ~90°F like ever is like

really cold

(btw motor temp ≠ esc temp)

3DS doesn’t offer spare motor pinions based on their website so your best option is changing out your motors.
reacher 6385 is good, you just need to double check that it will fit, iiiirrrrrccccccccc the overall length is 92mm? i could be weong tho someone’ll have to fact check that value

you can also double check your esc settings, maybe the temp cutoffs are too low and can be raised a little.

also double check your gear drives, they could be assembled without any backlash, causing more wear, friction, and heat. your seals can also lose lubrication, causing more friction

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Fatboy 320 trucks
FatBoy SS HD-MINI Helical Gear Drive 3:1
Plenty of space between the motors

They have backlash and they spin freely. My budget is not that great lol. I don’t think 3dservisas makes these drives anymore. Might have to switch to a set of Moon drives that I stashed away. Or buy different motors so they don’t get as hot?

Where are all the low gear ratio apologizers

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You think bigger motors would do the trick?