Something up with Mamba Max?
 

I have been running my MM in my truggy for awhile on 4s with CCBEC and fan, the problem is that i can run for about 5min. and it shuts off, i let it sit there for 5-6min, and i here the tones and i am able to go again. It does this over and over and it gets annoying when trying to race. It runs great between shutdowns though:lol:. Anyone know what the problem may be.

Sounds like it is thermaling. Mine used to do that in my Rusty when i was over geared for speed runs.

Yep, that's the thermal protection kicking in. The next time you take it out try to get a temp. reading right when it cuts out (otherwise the fan will cool it off before you get to it). My guess is the heatsink will be above 200 deg. F.

You could try adding an extra cap - this can lower temps some - what is your motor setup / gearing

Ok, it is geared 14/46, which according to the calc is 45mph. Would the front and rear diffs being stock fluid have anything to do with it (i filled the center with thick fluid and the stock fluid was grease, so....the front and rear is probably the same:lol:). I could get my new buggy running quicker if i determined that my esc isn't broken.

45mph would push the MM in a buggy on 4s. Doing the same in a truggy yields the results you have come up with.
The grease on the diffs might actually be removing some load from the motor/ESC. Diff oil would eliminate some of the slip that occurs with grease, basically giving more traction.

So would a smaller pinion gear fix the problem?

It should at least let you run longer between thermals, if it doesn't stop the MM from thermalling.

The calc says an 11t pinion would make it go 36mph.

i would advise against using a speed calculator to determine what gear to run. if you are overgeared now going down 1 pinion wont hurt your top speed compared what it is running now. most likely it will be almost as fast because you are working the motor too much.
if you are racing always gear for the speed your system can handle without going over the line or less if the track layout dosent require big speed.
post your motor and brand of truck also and then the guys can get a better idea if you are close on gearing.

I don't think you ever said, what motor?

It is a X1-crt with a Feigo 9xl.

Gearing for mid/high 30's with that setup should be ok - what are your motor temps?

Check for any binding etc on the drive chain - If you have not added an additional capacitor to the esc I would STRONGLY recommend this. I've had 2 MM blow up in this configuration 4s/mm 9xl prior to putting caps on. Since adding an extra 2700uf caps I've had no issues.

If it help or convinces you Mike does exactly the same thing - It is a $5 fix that lowers temps a fair bit.

I've never actually temped it, but if u put your hand it, it burns quite badly:lol:. I do use an rcm heatsink.

Sounds too hot then... I;d gear down some and look into that cap...

I would add a 40mm fan on the MM. I am running 39mph with great success on my emaxx. The fan makes a huge difference in temps for me. The 40mm fan doesn fit very nicely but it rests over the caps and the heatsink. I use 1 screw to keep it in place which makes for a flimpsy install, but it works. My temps on the MM dont go over 126 degrees in 100 degree days vs I was getting 150 ish range with no fan on 80 degree days.

I dont think the fan is an end all solution though a truggy is too heavy for an MM at 45mph.

If you want a nice clean install, the novak 25mm fan fits perfectly over the heatsink and you can screw it right into the heatsink and its very secure. You can use 4 screws right into the heatsink and its solid.

I think you are a bit overgeared too. Shoot for 40mph and you should be ok. As everyone has said you wont notice a big difference in top end and the MM will be happier.

Punch control also helps to get the amp peaks down so adding some will help with temps. People have had differing results but for me 100% punch control dropped temps by a bunch.

You can play around with motor timing, maybe use low if you are not there now, that will help with temps too. I have read though that the feigaos like a bit of forward timing and they are more efficient like this, but its something to consider.

Ok guys, i just ordered an 11t pinion and a capacitor from Mike:yipi:. One question though; where should i solder the capacitor on at:tongue:?

On the power leads as close to the board as possible. Strip a little spot on both and solder the cap there. Farther away lessens the caps impact.

How do u put shrinkwrap on it?

Either desolder deans (PITA) or just use electrical tape

I've used the liquid elect tape stuff and as long as you give it time to thoroughly dry, heat has never been an issue.

It's best to gear it so that your motor temps stay in check during your run, not for a certain speed (unless you're just making a quick speed run, then stopping). I had a 20T pinion on my Muggy when I first built it and that yielded some awesome speeds but I was pushing 150+ on my Neu after 5 minutes. Dropped down to a 13T pinion and now it is running 140 after 20 minutes.

Running 4s through an ESC only designed for 3s (don't let Patrick find out, he'll yell at you :tongue:) and pulling the amps you're pulling with that thing you definitely need a fan. Even just a little 25mm Novak fan will dramatically lower temps. I'd go for a nice 12v computer fan and solder it to the battery leads on the ESC though. The capacitor mod will also drop temps, so that combined with the fan and you should be in business.

I have a 30mm fan already, but i did order an 11t pinion, so i'm going from a 14 to an 11. Odd how just a few teeth can change temps:smile:.