I recently acquired a Redcat Volcano EPX 4x4 in a lot of used RC parts I bought on Craigslist. It has what appears to be a brand new Sidewinder 3 esc along with a Castle 1406 5700kv motor. Stock gearing 17/64.

The truck is a hoot on 3S, full backflips (not just wheelies) at speed with just a throttle blip. However, the fun lasts less than a minute because the ESC goes into thermal protection. Motor barely warm to touch.

An email to Castle resulted in them telling me the ESC was fine but the motor shouldn't be in a truck at all, and that was causing the overheating.

I've ordered a fan for the esc but I don't have high hopes, as this thing is literally a 45 second overheat machine. So...I'm wondering about these two options:

1. Replace sidewinder 3 with a $45 hobbywing ezrun 60amp esc . I have no clue if this will run the 5700kv motor ok.
2. Replace the CC motor with a lower kv, probably something like the Tacon 3650 3500kv.

Whatever I do, it needs to accept 3s as that's what I have most of. Trying to keep costs down as this will be a "loaner" basher for friends and family to use.

Whatcha think?

I've got a Sidewinder 2 with the 5700kv 1436 (4 pole) motor in a touring car, running on 3s. Even with a fan, the esc will go into thermal shutdown after a few minutes. Even though it can "handle" the power, it can't handle it with that motor. I've never tried a lower kv motor, so I can't say how well it'll work.

3s is really pushing it with the Sidewinder and a 5700kv motor in a 4wd truck.

I doubt the Hobbywing 60a would do much better.

To run that motor on 3s reliably you would need something that can handle higher cell counts and more current like a MMP or Hobbywing sc8. You can find sc8's for about 65-70 bucks on ebay.

A lower KV motor might help too. It will draw less current than a 5700 and probably not go into thermal protection. I have a sv3 with a Velineon 3500kv in my son's Rustler and it runs 3s just fine without any heat issues.

5700KV in a 4x4 1/10 MT on 3S with stock gearing is asking a little too much, to be honest.

Cheapest option, which is the best option IMO, is to gear it down a little (or get smaller wheels/tires), to maybe a 12T Pinion and a 70T Spur, which is common.
It will still wheelie & backflip, but it will have a little less top speed. And the fan does help by at least 20 degrees if it is always on.

Yeah, the HW 60amp won't do it. I had one on a Slash 4wd and with the Vxl 3500, it would just barely handle it on 3S. The heat on the esc would just creep up and up. Looking through Castle specs for that esc, 5700Kv is just barely in the 3S limits, and that's only with a light 4wd truck around max 4lbs. 5700Kv would be ideal for a 2wd. But for a heavier 4wd, that's really pushing it. http://www.castlecreations.com/suppo...5-0130-01L.pdf

I'm going to see what the fan does, but this thing is going into thermal protection on a 65 degree day and just puttering around in the street. No crazy hillclimbing or radical driving. And I'm talking seriously no more than a minute at a time. after the ESC has some heat in it I can get a couple of laps around my cul de sac and then it is thermalling again.

I guess i'll start with one of those sub-$20 Neewer brushless motors from ebay, saw one at 3900kv. Between that, the ESC fan and disabling the front wheel drive due to my blown diff, hopefully i'll be able to get a pack through this thing.

Hate to resurrect an old thread but my same esc motor combo has the exact same issue and I'm only running 2s.
I can't even finish a 5 minute race with this motor/esc combo and thats geared low at 18t pinion.
I'm gonna try a fan or maybe external bec but this combo should never even have been sold as a kit imho. This esc cannot handle the 5700 at all.
It will shut down between 130-160 deg no matter what motor you run.
Running when the weather is 100 outside it takes 1 minute to reach those temps yet the motor is at a cool 120-122.

Just an update- I bought a fan and Castle programmer. I moved the timing in the 5700 down from stock 10* to 7* and added punch control of 50%.
The esc now has good temps after a full battery run 119*, the motor will get very warm 158* but that's running a pretty aggressive gearing of 21/86.

This motor is made for stadium trucks and 1/16 scale and buggies under 5lb.
After talking to castle I ordered a 3800 and ran it with the same esc with a 23t gear, it equals the 5700 but has allot more torque.