Sigma.40

My Feedback: (1)

I was bored earlier so I decided to see how well my Slash 4x4 would work as a crawler (climbing over rocks, logs at low speeds) It actually did pretty well but when I was done I noticed that the motor was a little hotter than normal. Usually it gets only slightly warm, but this time it was hot. I could hold my finger on it for 4 seconds before the heat hurt my finger. I just read that the VXL gets hot at low speed but I couldn't find anything else about overheating that would answer my question.

Could the low speeds while climbing over rocks and logs have raised the temp. or is something wrong with my motor? NOTE- I was using a 2s 5400 MaH lipo and my gearing is stock. I ran it for 30 min and probably 20 of that was low speed

electricrc68

or because it was crawling there could have been a lot of strain going to the motor......im no expert but thats my guess.

Sigma.40

My Feedback: (1)

Thats kinda what I figured, since I was using it for something it wasn't meant for but I'd like to make sure.</p>

Sigma.40

My Feedback: (1)

In case it makes a difference, the esc wasn't hot at all.</p>

Haddi Taha

sensoreless brushless motors are not that good at low rpm anyway and that motor is more comfortable at higher speeds than crawling speeds due to its power curve. You should the gear it down so it runs more comfortably at lower speeds.

Sigma.40

My Feedback: (1)

It was a one time thing, I usually run it at high speeds in my backyard but wanted to see how it would do as a crawler.</p>

Haddi Taha

thats ok then as long as you constantly moniter motor temps and if you can't keep your finger on the can for seconds thrn its too hot. You should put a heatsink and a cooling fan it increases the longetivity of the motor because iff you overheat the motor your magnes will become weaker.

nitrosportsandrunner

crawler means slow speeds, which also translates into less air cooling of the motor.

this kinda stuff is where a temp gun is worth every penny. a vxl motor can run as hot as 190 degrees without damaging it.

when i ran my rustler vxl on a 3s lipo in grass/off road the motor would be 180-190 at the end of the lipo pack. ran like that all summer.

but you cant judge 190 degrees by hand. thats simply too hot to touch!

Sigma.40

My Feedback: (1)

So... in all likelihood it was hot because I was going slow?Also, if I could keep my hand on it for 4 seconds was it TOO hot? I'll be honest, this is my first brushless.

nitrosportsandrunner

if you could hold you finger on it that long, chances are it wasnt too hot.

but its simply not made to do what you were using it for.

now, VXL systems are used in crawlers, but are geared very low.

The_Shark

a motor going slow with resistance takes more power than a motor spinning at high rpm. its called counter voltage, faster it goes, more energy is fed back, and so less power consumed (acts as a generator)

low speed running and constant accel/decel is hard on motors, especially brushless as they tend to fight themselves at very low speeds.

nitrosportsandrunner

exactly. that is why for crawling guys gear the VXL motors waaayyy down. i have seen a axial scx10 with a vxl system running 3s lipo that WOT would only do 10-12mph. but that means that even at very slow crawling speeds the motor is turning a decent amount of RPMs.

Sigma.40

My Feedback: (1)

I feel stupid. I failed to realize that everytime I ran it before, the chassis was filled with snow so, of course the motor was cool. Now that everything is dry and it is in the 50's it was shocking to feel it that hot. Thanks for everyones help.

cooldriver385

The temperature outside doesn't really contribute to motor temperatures like it does to nitro engines. It contributes a little bit, but not much.

Sigma.40

My Feedback: (1)

Yes, but the 3 lbs of snow that eventually got thrown and packed around the motor did.