Take THAT Feigao!

[ElectricThunder]

Hopefully this setup will reduce heat drastically. It's been ridiculously hot this summer (the average temperatures in the past two weeks has been around 92F with anywhere from 40-100% humidity). The 540 8s geared 25/87 was running about 175F after a full pack of IB4200s.

It'd be great if I could get the Castle UBEC and crank the voltage up to around 6.5 or 7 volts (I think the mamba BEC is only 5v?). That'd A) give me more torque for steering, and B) spin both the ESC's fan and the motor's fan much faster. Plus I wouldn't have to rely on the internal BEC anymore.;)

I present to you....my crazy ass (and cheap) cooling setup:

[t3oc45]

You should have used a shwoogy...damnit ET

[ElectricThunder]

Yeah.....the shwoogy would lend itself to some better traction with its massive shwoogy weight.;)

[SS Pede]

LOL, that is the definition of "hack job." I like your style though!

BTW, isn't 25/87 a wee bit high for a Rustler?

What is a shwoogy?

[USATorque55]

Only in a Rustler.:cool:

Well done.

[ElectricThunder]

LOL, that is the definition of "hack job." I like your style though!

BTW, isn't 25/87 a wee bit high for a Rustler?

What is a shwoogy?

The VXL comes out of the box with 25/83, and the velineon 3500 motor is probably similar (if not the same basic thing) to a 540 10s.:p

Shwoogy is....well....it's a long story. LOL!

Just got back inside from running it and whaddaya know; temperature on the heatsink was 130F. Temperature on the actual can was about 140F (ESC was 120F). It's about 82-85F out and pretty humid (I'm sweating and sticky right now, so like, at least 50% maybe?). Tomorrow, if it's a nice hot day out, I'll test it and see what I get. If I can get it to run at 155-160F on the motor can during the day, I'll be happy. I think I may try a 9v battery on this fan for more airflow though....:D

Lipo would make this an absolutely PERFECT setup (and I'd probably be able to drop a tooth or two on the pinion while still maintaining close to the same speed, and thus decreasing operating temperatures a bit).

[chilledoutuk]

i originally thought that it was rpm that made feigao motors get hot but in the end I think its just the efficiency of the motors under high current applications is well crap.

when it comes to feigao motors it gets to the point you can go crazy trying to keep the things cool now when i have to run a feigao i treat them as disposable motors. Meaning run them and as long as there not melting your car who gives a crap what temp there running If they demag then bung them.

If my cm36 7700 overheats and demags on 6.6v 2s2p a123 castle know they will be getting a motor to fix.

[ElectricThunder]

I've taken the same attitude, but I figured it'd be kinda fun to try this.:D

Today I'm going to try a 9v battery setup and test it during the day (in about 10 minutes from this post time). It's hot again today, and it rained earlier, so humidity is probably nasty (not sure though; I haven't exactly made it a point to stand outside ya know?;)).

Woohoo! Ok, so it was in the mid to high 80s I think (probably closer to about 90F even). The ESC temped at 125F at its hottest, and the motor can itself was at 140F at its hottest (it ran at around 135F most of the time). The heatsink on the motor was around 120-130F a majority of the time.

Oversized fans FTW!

[Big House]

ET... is nice to get a big fan in there but making it look good is the hard part.

[SS Pede]

If my cm36 7700 overheats and demags on 6.6v 2s2p a123 castle know they will be getting a motor to fix.
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Hey how's the performance on those A123's?

[chilledoutuk]

performance is good they seem to be able to handle the 7700 easily but there voltage does drop more so you need to gear up a bit.

The cells handle the power demands easily and barely get warm.

The 7700 has such a high kv that even on 2s a123 the motor still hits 50k which is higher than the 5700 on 2s lipo.

The motor seems to run cooler but the after a while running the motor does get quite hot in the cat 3k due to the lack of airflow with the shell on and because of the transmissions openness venting the shell is difficult.

On a 2wd offroad car its much easier to actively cool motors and thus i think in that situation the 7700 on 2s2p a123 would be a good combo but make sure you put a fan on the mamba max as the current it has to pull to make high rpm is substantial.

I have those a123 cells setup as two separate packs that i parallel or connect in series depending on the application. which effectively means they can be either 2s2p or 4s1p.

I run 3s1p on a plettenberg extreme and mamba max losi xxxt setup which is a little more demanding and after a run the cells are quite warm but nothing to be too concerned about.
Even though the current draw might be asking questions of the cells its still powerful enough to force me to have to rebuild the transmission twice already (i have cranked down the diff this time though:).

[scoob]

You guys are going to freak but I had a 540 9L sitting around doing nothing and decided to put it in my stampede on 2s lipo. I actually love it. I've been looking for a motor to run in the pede that will stay cool. This truck is harder on motors than anything I have. It's a long story but I am bored today.

I've had a Novak 10.5, 540 8s, mamba 4600, 5700, and most recently a 380c 9t in the pede. The novak was about right and ran good temp wise ( I don't like a lot of power in the Stampede due to wheelies) but for some reason it didn't like the radio and glitched the servo. The 540 8s was OK but too violent. The Mambas ran hot and the 5700 was overkill. The 380c 9t was about perfect but required a 15t pinion to keep temps in check and the small pinion caused me to strip spurs as I couldn't line it up to mesh with the width of the spur due to the set screw. With the 9L I can finally use a decent size pinion which works so much better with no set screw in the way. The loud meshing sound is gone now too. The motor turns just over 20,000 rpm on 2s lipo and at 23/87 is pretty fast. Doing the math it should top out close to 30 mph. Gobs of torque and the top speed suprised me given the 2731 KV. The motor just bumps along and temps were just warm at 130 F after a long run in grass on a hot day. The mamba ESC didn't mind it either at 138 F. The weight in the rear didn't seem to make it terribly wheelie prone either, could wheelie if I wanted ut could also get on it pretty hard. I could gear up a lot if I wanted but I'm afraid it would turn into a wheelie monster.

It's really quiet compared to what I'm used to. It's deceptively fast because the motor sounds so tame at the low revs. It sound like it's barely reving but the truck is hauling pulling wheelies throughout the rev range. I'm used to brushless motors screaming to move the truck along decently but the big motor just lugs along. It would look stupid in a buggy or something but looks kind of cool in the stampede with that "big block" sticking out.:D
Anyway just an experiment I thought I'd share that sort of fits in the theme of this thread.:)