motor and batteries stay cool, esc gets hot

standard_63 · #1 09-21-2005, 02:03 AM

I just got a warrior 9920 and a Nemesis 6xl and am running 4s lipos in my Emaxx, and finally have cool motor and batteries but the esc is getting real hot after about 2 minutes. Since the motor and batteries are cool I don't think it's drawing too much current, what could be the problem? I'm running all UE parts and 40 series mulchers with 14/51 gearing. This motor is a torque monster so is supposed to handle bigger gears, but would gearing down help? I origionally tried a 16/51 but after 14/51 the motor was warmer...also I am locked in 2nd gear with gmaxx 1 speed conversion.
Thanks for any insight!

e_lm_70 · #2 09-21-2005, 09:49 AM

Are you using the BEC of the 9920 ?

I guess the BEC is making the ESC Hot ... since it has to absorbe a lot of power ... from 14V down to 5V ... with around 200-700mA ... so around 5Watt constantly ...

e_lm_70

standard_63 · #3 09-21-2005, 10:00 AM

Yeah, i am using the built in bec. Also have a pretty hitorque servo (280oz), so I'm going to try a ubec tonight -- I hope that does it!

tcolesen · #4 09-21-2005, 05:32 PM

You may still experience a lot of heat, as the 6XL is a very amp hungry motor, and can easily pull more amps than the controller will put out.

standard_63 · #5 09-21-2005, 05:57 PM

Grrr...Chris Fine sold me this combo saying it was a good match for 4s lipos and my setup, but I guess it's not. I ordered an MGM 16016 today--another day in debt I guess...

At least now I have something to run in the MT2 coversion I want to do, just gotta get the MT2 now!

tcolesen · #6 09-21-2005, 07:54 PM

You're running a 6XL in a MT2!?!? I think a Feigao 12s would be a better motor (not so heavy!) for a MT2. The most I would put in one would be a Feigao 8L on 4s Lipo.

standard_63 · #7 09-22-2005, 02:12 PM

No No, the 6XL will stay in my Emaxx, but I will probably end up using the 9920 in an MT2 if I get one. A Basic 4200 should probably do an MT2 ok, right? I do also have a Feigao 10L I could use, but I was thinking that would be too heavy.

starluckrc · #8 09-22-2005, 07:03 PM

I have a converted MT1 with 7S is interested.

TimisTim · #9 09-22-2005, 07:15 PM

Go with a lehner 2400xl or other equivalent in kv for a 4s lipo. Chris Fine is a jack*** if he told you to run a 6xl on 4s lipo. Did he think it was a boat with a huge prop or something! I just snapped the motor shaft on my feigao 8S in my MT2 so I will be switching to the Lehner 3600xl or the new 540c 9L from starluck (on 3s lipo).

standard_63 · #10 09-23-2005, 05:25 PM

Funny thing that when I called Chris to ask about my problem he acted totally surprised I was running a 6XL. And then he told me my problem was the 4s lipo.

I told him what I had before I ordered and he recommended 6XL/9920!! All he said is I might have to play with gearing.

So should I swap out the 6XL for a 7XL maybe? Would that be ok on 4s lipo?

I don't think I can do the MT1 or 2 right now as I have just blown more than I should have for two whole BL setups -- not feeling good about RC $$$ right now...

tcolesen · #11 09-23-2005, 07:23 PM

The 7Xl wouldn't pull as many amps, so the controller would stay cooler.

standard_63 · #12 09-23-2005, 11:31 PM

How about a 10L? Is it an option? I already have one of those.

glassdoctor · #13 09-23-2005, 11:43 PM

I think the 10L is a very good motor for an emaxx and 4s lipo. The motor can handle itself and the esc will do much better. Try your 15/51 gearing to start with... it should run pretty well in 1st gear and maybe pull 2nd.

That's about the same gearing I ran mine at... locked in 1st gear with C50 3000kv. You can probably gear up from there, or run in 2nd gear for speed.