Gearing on an E-Maxx with a 7018 and _ Motor (also picking a motor)

[Red350DropTop]

I don't understand how you need to gear a setup to prevent thermaling. Is their a formula I can use? I found one recommendation to keep the E-Maxx at around 18:1 gearing. Is that true? Why doesn't that apply for the HV-Maxx, but it does for the 7018?

Also, from what I can tell I could use anywhere from a 9L up to a 10XL and still be OK based soley on amperage draw. I plan to use 12 and 14 cell packs. Yet, I know that I could overgear the truck and fry the ESC.

I guess I don't understand why I couldn't pick say a 12 L and then gear the truck to get the speed I want... does it have to do with starting out torque?

Any motor recommendations or am I fighting a lost battle with the 7018?

[Gustav]

Welcome to the forums!
The 7018 can be used in the e-maxx but it's right on it's limit's so your right,careful gearing and motor choice is needed.Coolhand has run the 7018 i think,i believe it died in the end,he'll be able to advise you.
Do you have the controller already?
I'd guess a 10L might be a good motor,or a lower kv XL motor like an 8 XL.Running more cells with a lower kv motor should bring the amp draw down,so it might be better to run more cells with a 12L or a 9XL.Running the 12L on just 12 or 14 cells and higher gearing should draw more amps due to the higher load.

[maxxdude1234]

I use a 7020 in my truck. With a Basic 2000xl on 18cells it run fairly cool. I wouldn't run anything hotter than a 10L/9XL with it. Like gustav said, aim to run a higher turn motor on a higher voltage with a 7020.

[coolhandcountry]

The 9xl seems to work with a lower gearing. Depends on the size of tires the cells you run and the diffs you have. I had a 14L on one that works well to. But you can't get crazy with gearing.

[Red350DropTop]

So the only way I use a 7018 is to use higher than 12-14 cells. What do you guys recommend?

I can get a new 7018 for $125. Mike isn't listing them anymore on RC monster but I would be interested if he can still get them (especially at that price). I don't know if a 9920 is worth another $75 bucks (but maybe it is).

Coolhand and MaxxDude what gearing are you running?

[maxxdude1234]

I run 18/72 with my 2000XL

[coolhandcountry]

15 51 work well in a monster gt with big joes on it and 14 cells. That is with a two speed trans though and 9xl.