Causes of hot temps

[Robert]

Someplace there was a post listing most common reasons for heat. My MM has begun to run hot lately and I'm trying to figure out why or what I can do to lower it. It seems to run fine if I run it hard. However if I'm going real slow or using the brakes it heats up. I know don't go slow or use the brakes.

When I bash with my neighbor he has alot less room so we need to go slower.
It's in a slash MM5700, 14/90, running a 3s.

[Arct1k]

3S can be quite a bit for the BEC to step down - You could look at an UBEC

Secondly what is condition of your capacitors - How old are they? Do they show signs of damage? Might be worth looking at adding a new bigger cap such as the Novak HV 2700uf.

Also a 5700 is a reasonably "hot" / ampy motor anyway...

[Robert]

Everything is new, about 20 runs on them. I have a BEC but becaause of the way the failures happen I've been scared to use it. I don't want to fry my electrics (IF) it fails but, I guess that's the best option.

[Finnster]

A lot of the times heat is released due to inefficiency of converting battery power to mech power. Elec motors, esp cheap ones actually lose eff quite a bit when they are ran lower than their ideal load ranges. Ie light loads, like running slow, causes eff to fall and more power is wasted to heat. Too much is load is usually thought of, but low loads are often forgotten. Some of the worst eff% are at low loads. Usually not too big a problem as the power levels are low, so actual heat units are still low enough to be ok.

EG. When I had a cheap fiegao in my Revo, it can run cool doing speed runs and fast running in dirt. Now if I went to go slow over big rocks, then the heat shot up fast even tho I was just putting along.

Solutions: well getting a good motor is always the best help. Medusas are great for not much money. Otherwise try playing with the gearing until you find something that works.