Heavy Emaxx, big tires, 10L motor -- need controller

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I started out with the Hacker Maxx setup a couple of years ago(C50 Maxx, Master Comp controller) and since that setup ran so hot I didn't run it too much. I decided to try upgrading the motor and that helped a lot, but the controller is just getting too hot. (only rated at 80A and I have the BEC version but BEC is turned off)

The truck is probably 13lbs+ -- all aluminum Supermaxx with 40HD series Mulchers -- geared at 14/51 with reduced gears in the diffs due to SM 1/8 diffs and 4s 6000 lipos. I also tried 16/51 to see if I was pulling too many RPMs, but the controller shut down even faster, but the truck was very fast!!

So, in order to get a more bulletproof runtime out of this thing I'm thinking of the 9920 or one of the 20120/150A models for more $$.

My question is how much more robust would the 9920 be over my Hacker Comp controller? Would I need a fan on this setup? How about with one of the 20120/150 controllers? Would I have enough headroom with one of those to prevent thermalling my setup, or would it just be overkill?

I don't see myself setting the truck up to be any faster, it already goes much faster than I can controll, but I would like to be able to plug and play anytime I'm in the mood to run, which I can't really do now for more than 5-10 minutes at a time. I would like to run up to 1/2 hour if possible, just bashing, not racing.

Any input would be appreciated!
Thanks!
--Jonathan

[MetalMan]

The Warrior 9920 should be a good controller to use. If it got hot, then a fan would cool it down. I don't see a need for more than the 99amps continuous that the 9920 has to offer.

Half an hour runtime will be a little difficult to attain with 6000mah. Your truck is heavy, and so either speed or runtime are going to be decreased (as opposed to a lighter truck with a 10L and a 4s 6000mah battery).

That's a heavy ride. :-)


I would suggest that you first get a temp gauge (about $25) and measure your temps.

The first "low cost" solution would be a fan and heat sink. Try this out and test your temps.

You can get more runtime a myriad (w/ different combinations) of ways; less weight, lower gearing, more mah, more voltage, etc.

What you choose is up to you, though if you're looking for a low cost solution may want to relinquish top speed (i.e. bigger spur) for runtime... just depends on your budget and goal (doesn't it always? :-D).

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Yeah, that aluminum feels pretty light in the packages, but all assembled it sure does add up!!

With my C50 motor and my smallish backyard track I was getting pretty close to 1/2 runs a couple of times, but now since I've added a triple jump that needs some speed to clear my temps are getting up there on the esc. The motor was at about 158f and the esc was close to the same on the heatsinks. The motor seemed fine at that temp but the esc shutdown for a little while.

My main concern for runtime is not overheating the controller, I guess 1st I'll try a fan on the controller I have now. I can always get bigger batteries, but if they will only run for 5 minutes it doesn't matter! Maybe i'm just wasting my time on this thing and should just stick with the Revo...

Which C50L do you have...how many turns? I.e. C50 6L, C50 7L, C50...?

[edit]
nm. Its in the subject. :-)
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[coolhandcountry]

Did you try going back to a 12 tooth pinion? See if that helps. You say it runs faster than you can control. This should help with esc temps some. I see a lot of people run a 10pinion and 51 spur. Just a suggestion.

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The smallest pinion I have right now is 14. I was thinking of ordering a 10 and 12, but from what i have read on here I'm confused as to whether more rpms would run cooler or not. I would think it would, so I'm going to try the 14 pinion tonight with 12 GP3000 cells and see if it runs cooler than with the lipos. I do have the heatsink/clamp but should also get a fan. I also am going to try stock size bowties and see if that helps -- it should at least take 3 or 4 pounds off!

I have the C50 Maxx motor, which I think is a 12s? It would get reeaally hot.

[coolhandcountry]

The stock size tires sounds like something to try. Less weight seems to equal less heat. Shorter tires will also gear you down some. Try one thing at a time though. If you try a group of things you won't know what fixed it.

[MetalMan]

You will gain back some of the weight when switching to GP3300's, though. But it might run cooler, since the higher resistance of the GP3300's will cause more "give" (if you will) than the Lipos.