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Old 06-26-2016, 10:57 PM
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Originally Posted by Maj_Overdrive View Post
I ran the gear calc on your combo, even on 6s that's about 60mph theoretical. You want 85kph or 50mph which it shouldn't have had any problem doing and it really shouldn't have gotten all that hot either. I've run that motor in other truggies geared for about 55mph and maybe it would hit 180F when beating on it hard in really tall grass. There's no reason the 1515 shouldn't have been able to handle this combo, if anything maybe it could've used a heatsink and fan. But if you want a more powerful motor it needs to be bigger, either larger diameter and/or longer. In 40-42mm diameter have a look at Neu 1521 or 1527, Poseidon's 1527, Track Power 4070 (NOT Turnigy Track Star), or Leopard's 4085 and 4092. All are 25mm mounting. There's also the Castle/Traxxas 1717 from the XO1, but it's just under 50mm diameter requiring the center diff to be raised with a spacer.

The only time I've ever seen temps anywhere near yours was an old 2pole Feigao I overheated a bunch of times. Then I purposely way way way overgeared it and proceeded to thrash it for scientific purposes but never saw anything over 275F.
Does dry dust/dirt cook motors? I kicked up alot of dust with the car, Only difference of between the runs that were normal and the really abnormally high temps.

Does this graph look right? http://imgur.com/NJYPSGp and http://imgur.com/Y0oEStx

First 3 thick vertical red lines are just "Motor start failure" warnings and the last one is just a "Normal Boot-Up Sequence" that is when i stopped and noticed the 160c degree motor temp. The horizontal pink thick line says "Temperature Cut-off 115.00 Degrees" and the thick red horizontal line is the LVC which is set for 3.4.

I am just so puzzled why this setup even blew up my motor.

Last edited by David87965; 06-26-2016 at 11:00 PM.