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Old 09-11-2007, 08:50 PM   #1
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Velineon running HOT 200(F)+ on 3s 5 amp lipo

The Esc hit 205 and the motor was 185 after running it on pavement. I was running like I would on a dirt track with 50 - 75% throttle, braking turning and back on the gas. I'd say I ran it for about 10 minutes and it was only 72 degrees here today. The ESC started to malfunction when I tried to turn it off (never had a problem while driving it). I held the button down to turn it off, the light would go out and then turn back on to solid green. It refused to turn off until it got down to about 180 - 185F.

Isn't that running too hot for such light load running? I do have it geared to pull 65+ but this was on a level paved road.

To help it out I'm going to look at good CPU heatsink / fan combos. Can I just pry the current heat sink off without damaging the ESC?
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Old 09-11-2007, 08:56 PM   #2
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Running it at 50-75% will cause a lot of heat, Mopst all brushless ESC's and motors are best at full power. Also the 3s is a heat builder as well, With stock out of box gearing mine got to 168* on motor but esc was at 110* on 3s. Its also possible you got a wheel or a gearbox too tight and causing a drag that will help heat things up, Pull the pinion off and see if there is a restriction somewhere in the drive line
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Old 09-11-2007, 09:02 PM   #3
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Running it at 50-75% will cause a lot of heat, Mopst all brushless ESC's and motors are best at full power. Also the 3s is a heat builder as well, With stock out of box gearing mine got to 168* on motor but esc was at 110* on 3s. Its also possible you got a wheel or a gearbox too tight and causing a drag that will help heat things up, Pull the pinion off and see if there is a restriction somewhere in the drive line
Yeah, I'll look at the wheels and gearing again but I did check everything after putting the new pinion and spur in (it got up to 165 on stock gearing and the wires to the motor were hot to the touch). The truck also rolls freely if it's sitting on slight incline.

But since your ESC was only at 110 with the motor at 168 something is definitely wrong with mine. Were you running with the body on?

If I can't run it at 75% throttle I'm going to have fry that slipper clutch because the thing can't stay on the road at 100% lol. Guess that's one benefit to a nitro truck, I didn't know that partial throttle was a problem for brushless power.

Thanks
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Old 09-11-2007, 10:03 PM   #4
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You can't stab the throttle on 3s, you got to use a little control. I have run my Stampede VXL on 2s and 3s since i got it, and haven't got it to overheat. You can get to 100%, just can't right now, you got to roll up to that speed on 3s. Personally i think 2s is better for the truck (stampede, not sure what your is) but the way it runs across a grass field on its rear wheels makes a 3s run every once in a while fun. I'd run 3s only once in a while, Because if you go over 200* too often, the motor will demagnetize and cause the esc to heat up more. BTW what truck you got and what gearing? It wouls be easier to guess the problem if we knew what you had

Oh and the 168* on motor with 110 on esc, that was after 30+minutes of runing on a 3s 5000 Maxamp pack
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Old 09-12-2007, 07:24 AM   #5
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I don't stab the throttle, I progressively work up to 70% because of traction and wheelies. I'm running the 31 pinion / 72 spur gears in the rustler. If I stab the throttle it'll be upside down in .1 seconds

They said it can handle a 3s Lipo.... I'm going to get a better heat sink and cut a hole in the body to feed more air to it (like a nitro truck). There's also a connection to add a fan, which means they know it can overheat even when using recomended power and gearing (even while running on level ground with minimal resistance).

Maybe I'll look at the 6amp 2s2p pack from maxamps for a second battery. How fast will it run @ 7.4 volts?

Thanks
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Old 09-12-2007, 12:44 PM   #6
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That gearing is too high for bashing, you need more like 25/86 for straight bashing. that gear is good for high speed but you need to let it cool every 5 minutes or it will damage the motor and or the esc
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Old 09-12-2007, 08:29 PM   #7
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I think cooling every 5 minutes is ridiculous and it's supposed to have a high temp shut off to prevent damage (guess it's over 200F). I'm going to get a heat sink for the motor and a better heat sink for the ESC and I'll cut a hole in the body.

The truck is a lot of fun but I don't think Traxxas should advertise that a truck is capable of something if it's only for a few minutes on the street.

Having said that, I'll probably put the stock gearing back in because 70mph is too much speed for the truck, or my local track.
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Old 09-12-2007, 10:25 PM   #8
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You can't expect any vehicle setup to run nice and cool and work for general bashing when it's geared and volted for the bleeding edge of performance. I don't think Traxxas is out of line by stating what it CAN do when setup to the max specs. They do make some effort imo to say that the 60/70mph setups are extreme and not for average use.

A 5000hp +300mph drag car can't run laps at Daytona for the same reason.

I am actually impressed that it didn't get hotter and shut down before your 10 minutes.

btw, those temps are hot, but not so hot they will do damage. Keep the motor under 200 and the esc is ok as long as it doesn't shut down.
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Old 09-13-2007, 07:00 AM   #9
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I understand that it should get hot and I didn't think there was a problem until the ESC wouldn't turn off. Had it not malfunctioned when I tried to turn it off I wouldn't have thought to even check the temp.

I didn't know that a 3s lipo is too much for an electric RC. I just read the promo / hype and expected it to work, which it does, it just gets hot with the tall gearing. I'm going to switch back to stock gears and not worry about heat buildup.

I'm use to running nitros and when they're tunned ok they can be run for as long as you want. I didn't know electric had extended run time problems.

Thanks
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Old 09-13-2007, 12:39 PM   #10
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run it at 100% it will cool it down, less drag brake=less friction
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Old 09-22-2007, 06:04 PM   #11
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I ran it today in my backyard with 31 pinion and the stock spur (83T?). I kept it at 100% throttle except for when I made a turn but the temps were higher this time. It ran for <10 minutes and the motor hit 221F the ESC was also 221F and the power lines to the motor were 154F. I double checked all the moving parts; gears, wheels, etc and nothing is resisting movement. The ESC was blinking green and wouldn't shut down until it hit about 170F (like last time).

I still haven't changed the heat sink on the ESC but I think I'll just give up on the 11.1V lipos and try the 7.4V's.
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Old 09-22-2007, 10:31 PM   #12
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Originally Posted by R1R 7humbs View Post
I ran it today in my backyard with 31 pinion and the stock spur (83T?). I kept it at 100% throttle except for when I made a turn but the temps were higher this time. It ran for <10 minutes and the motor hit 221F the ESC was also 221F and the power lines to the motor were 154F. I double checked all the moving parts; gears, wheels, etc and nothing is resisting movement. The ESC was blinking green and wouldn't shut down until it hit about 170F (like last time).

I still haven't changed the heat sink on the ESC but I think I'll just give up on the 11.1V lipos and try the 7.4V's.
You're still geared too high, you need a 25 or lower to get best results. I got an SRT (predecessor to the rustler and virtually identical) geared 23/86 and it has no trouble runing cool, I don't run 3s lipo all the time, but when i do i don't have the troubles you have
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Old 09-22-2007, 10:58 PM   #13
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You're still geared too high, you need a 25 or lower to get best results. I got an SRT (predecessor to the rustler and virtually identical) geared 23/86 and it has no trouble runing cool, I don't run 3s lipo all the time, but when i do i don't have the troubles you have
I want the truck to keep up with my nitro stuff, so I can't gear it much lower.... but I'll but the original 27 tooth pinion back in (it still ran hot with the stock gears).

I'm disappointed in the truck. It truly handles like crap compared to the 4wd 1/8th scale nitro buggies we have (rear wheel braking isn't good). I wanted to try the electric stadium truck because it was supposed to be fast with less maintenance... No big deal, I'm going to keep running how I want to and if the esc or motor dies, oh well. After that happens, , I'll stick with the buggies and hopefully there will be a 4wd 1/8 scale brushless version on the market by then (I'm not sure about getting / doing a conversion kit).

I'm pissed off with the truck and I probably made a mistake hooking it up to the 3s lipo. It's a joke because it can't put the power to the ground anyway so I probably should have gone with the 2s 8 amp pack, which should be able to keep up with the nitro stuff. At this point I consider the batter and steering servo to be the two good pieces of equipment in the truck. I just should have done more research before buying...

Last edited by R1R 7humbs; 09-22-2007 at 11:11 PM.
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Old 09-23-2007, 12:43 PM   #14
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Originally Posted by R1R 7humbs View Post
I want the truck to keep up with my nitro stuff, so I can't gear it much lower.... but I'll but the original 27 tooth pinion back in (it still ran hot with the stock gears).

I'm disappointed in the truck. It truly handles like crap compared to the 4wd 1/8th scale nitro buggies we have (rear wheel braking isn't good). I wanted to try the electric stadium truck because it was supposed to be fast with less maintenance... No big deal, I'm going to keep running how I want to and if the esc or motor dies, oh well. After that happens, , I'll stick with the buggies and hopefully there will be a 4wd 1/8 scale brushless version on the market by then (I'm not sure about getting / doing a conversion kit).

I'm pissed off with the truck and I probably made a mistake hooking it up to the 3s lipo. It's a joke because it can't put the power to the ground anyway so I probably should have gone with the 2s 8 amp pack, which should be able to keep up with the nitro stuff. At this point I consider the batter and steering servo to be the two good pieces of equipment in the truck. I just should have done more research before buying...
You are trying to keep up with a 1/8 buggy? Good luck, that's like a mini cooper keeping up with a Mclaren. Its possible to keep up in the corners, But you will get eaten alive on the straights. "Fast with less maintenance"? Yes, within its type and range. You are not going to beat the buggy anywhere, but a parking lot with the truck. I am sorry to say it, that way, but its not going to happen. On the good side, with stock gearing you should be good against Nitro trucks in its class.
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Old 09-23-2007, 07:34 PM   #15
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You are trying to keep up with a 1/8 buggy? Good luck, that's like a mini cooper keeping up with a Mclaren. Its possible to keep up in the corners, But you will get eaten alive on the straights. "Fast with less maintenance"? Yes, within its type and range. You are not going to beat the buggy anywhere, but a parking lot with the truck. I am sorry to say it, that way, but its not going to happen. On the good side, with stock gearing you should be good against Nitro trucks in its class.
yeah... it's my brother... he has a sweet mugen mb5r with the c6 t7... I got destroyed lol. I can't really beat it on the street either without a wheelie bar but the truck does jump well. I'll try to get him with an electric 1/8 scale buggie
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