aittam

Hello,

I'm using the MM 5700kv on a 4wd buggy (Tamiya DB01), with lipo 2s 5000mah 25C.

The motor keeps overheating, no matter what i try. Luckily the esc has never shut down so far. There is no space under the body for a cooling fan or a heatsinkor to put on the motor.

The body shell is as open as possible. Any more than that and i could run with the body off.

The other day (midday, 32°C) with 17pinion and 91spur gear (FDR 10,97):
- after 7minutes of racing the motor was 75°C and the esc 65°C
- after 25minutes of racing the motor was 91°C and the esc 75°C.

Yesterday night (10pm, 23°C):
- with 16pinion and 91spur gear (FDR 11,66):
after 10minutes of racing the motor was 64°C and the esc 52°C;
after 20minutes of racing the motor was 81°C and the esc 62°C.
- with 15pinion and 91spur gear (FDR) 12,44):
after 10minutes of racing the motor was 80°C and the esc 51°C;
after 20minutes of racing the motor was 81°C and the esc 53°C.

I cannot make the motor run cooler than this.

I'm worried that even if I stay with the 15 or 16 pinion and go racing on a hot day, i will get much higher temps.

Do you have any idea what else can i try? Should i try a bigger pinion? Or a smaller one?
If i try a smaller pinion i might run it too undergeared.

Thanks.
Mattia.

Hyde

iTrader: (1)

Those temps aren't very high. Motors get hotter then that. Those gear ratios are very high. I wouldn't worry about it.

If you can't touch the motor more then 3-4seconds then yes to hot, gear lower (if possible) or modify a heat sink

geeunit1014

iTrader: (14)

Like Hyde said, those temps are not outrageous, especially considering the amount of time you are running. One other thing to try, if you have any timing in the ESC settings, turn it down. I would try to keep everything under 95*C. Another thing to consider is if you can, you may want to cut a cooling hole in the body

aittam

Thanks for your replies.

I cannot touch the motor for more than 1 second after a 20minutes run.

A 15teeth pinion is the smallest pinion i have. I don't think a 14teeth pinion will fit in there.

I did not modify the timing setting on the Mamba Max esc. It is set to Normal (10). Should i try Low (5) or Lowest (0)?

If i cut any more holes in the body shell, i don't think it could be called a "shell" anymore.

Regards.
Mattia.

geeunit1014

iTrader: (14)

Go to the lowest timing setting. It should help. Also, try a heatsink on the motor, that will definately help drop a few *'s

aittam

Hello again.

I've been playing around with the timing settings of the Mamba 5700 motor, trying to figure out how to reduce the temperature.

Yesterday night (10pm, 27°C):
- with 15pinion and 91spur gear (FDR 12,44), timing set to Lowest(0):
after 10minutes of racing the motor was 75°C and the esc 57°C;
after 20minutes of racing the motor was 91°C and the esc 64°C.

Now I'm stuck. I don't know what else to do.
Any idea?

I've found another post of guy having the same overheating problem, he contacted Castle Creations support and they replied that the Mamba motors can stand up to 250F/300F. Could it be possible?

Thanks.
Mattia.

Duster_360

iTrader: (21)

I've been running a Sidewinder/5700 combo in a Slash. Have basically seen the same thing in trying to keep it cool, no matter what gearing, it runs hotter than I'd like it too.

We've been told 200F is OK for these motors in a Castle thread on RCM. Mine is running 175-185F so I guess I'm supposed to be happy with that temp.

beemerfan

iTrader: (39)

Can you fit a bigger spur and get your FDR around 15:1? That should cool it down and then you could go up pinion teeth from there. The 75 degree C temp seems okay, but if you are going to run for extended times, you should work more on that gear ratio.

aittam

I sent an email to Castle Creations customer support.
Got a reply from Joe Ford. He said that if i'm already using the smallest pinion, the biggest spur gear and set the timing to Lowest (0), then that's all about i can do.

Mattia.

geeunit1014

iTrader: (14)

One thing to consider is that your running for 20 mins straight with a fairly high power system. Im actually kind of suprised its not any hotter (Its still under 200*F). I wouldnt worry about the ESC temps, those seem fine. If I was you, id figure out a way to get a fan on the motor, that will make the biggest difference in temps. You can try reducing brake/drag brake as well, but im not sure it will make a whole lot of difference given how long you are running.

Hide

iTrader: (8)

Remember that you can be under-geared as well.

Duster_360

iTrader: (21)

Tried changing both directions in my Slash, a little and a lot - gearing up made 5700 run even hotter.

aittam

Yesterday i went to a new track, way much bigger than the one where i usually race/bash. The main straight is 40m long compared to 15m of the other track.

With my usual setup (15pinion and 91spur gear (FDR 12,44), timing set to Lowest(0)) after 10minutes of racing the motor was 65°C and the esc 49°C.

I'm starting to think the problem was not in the motor itself, but in the track that is too small for the 5700kv.

Maybe i should start looking for a 4600kv...

Mattia.

losi eight

I was wanting 2 know if some one can help me out. Please! I'm running a sidewinder 5700kv motor on a slash. I know its to much. But I like it. I like power and a lot of it. At first I was running a 58t spur and a 15t pinion. 32p. And it was getting so hot it was shutting off. So know I'm trying 90t spur and a 12t pinion. 48p. It still gets hot but does not shut off anymore. I feel like I'm stuck with this gearing. I would like to drop the temps a little more. Can someone help me out. Thanks! Sorry I'm having the same problem! I'm new to the forum couldn't find were to post a thread.

Lazer Guy

iTrader: (1)

Over the last 5 years I have been running the MM 4600, 7700 and the 9000.
I've found with a temp gun you go by the ESC temp to find the sweet spot.

If your ESC is cooler then the motor ...... you need a bigger pinion.

If your ESC is hotter then the motor ......you need a smaller pinion.

The sweet spot is when your geared so there both the same temp +/- 15* depending on grip and timing.
My 4600kv it was 145* ESC and motor.
7700kv .....180* both.
9000kv .....200* both.

Low timing is hard to drive (to much Rip) Timing at (15) moves the power band up so it's easier to drive in slower parts of the track.

If you have to do some grinding to get a bigger spur or smaller pinion on thats just how it is.

I hope that helps you some