Sidewinder Getting HOTT and cutting out!

[Twisted Nuts]

i tried a search for this but came up unsuccesful
anyhoe, i'm running an MRC with
sss chassis, sidewinder micro, TMM, and an eflite 3cell lipo.
after about 5mins of crawling the sidewinder is so hott it cuts off momentarily, but if you just drive around it's fine!!
anybody have a clue?

already checked axles and gear mesh

[JOMJ87]

BY hot is is hot to the touch? mine has never ran hot but it was on NIHM 3s may be doing it? especially since its not in a case with heat sink.

Cole

[soundcolor]

Don't think that esc can take a 3s.

[JOMJ87]

It is rated to take 3 cell from Castle but they may be a bit to much depending on the motor setup (22T??) and how much power it demands.

Cole

[Crawl_Before_Walking]

I run tmm 33t on a sidewinder micro and use 2s with no issues and has plenty of power like that, try running it on 2s, the esc IS rated for up to 15v but with no heat sink I doubt it would take that kind of voltage for long. Also change your wiring for thicker guage than whats on the tmm as standard and use good connectors (small coralies or mini deans).

Finally, make sure its in a place where its got some airflow around it and not jammed into a tight hole with something else IE BEC right next to it.

[Arct1k]

Are you using a external BEC - The internal BEC has to scrub a lot of current i.e. heat on 3s and will cause it to cut out...

Driving around my guess is you are not loading up the servo much but crawling you are... I guess you are probably using a full size servo too... Poor ESC ;)

[Twisted Nuts]

Thanks for all the replys.
I'm running a 33T, it had a castle brushless motor on it and never had an issue. I'm running a 9T pinion, no I'm not running a BEC, or a full size servo, I'm running a HS5245MG. And yes the ESC gets hot to the touch! But the motor don't, Ive been running 3cell since this truck was born and havnt had any issues until I went to brushed.

[Arct1k]

Its the BEC cooking on 3S - Try with external BEC and I think your problems will go away...

[Twisted Nuts]

I'm gonna get a CC BEC! But if that was the problem wouldn't it have done the same thing when it was BL?

[Crawl_Before_Walking]

Heat can be cumulative - the bec may have been warm but the fets for the motor side may not have been, the TMM may draw more power than the brushless motor was drawing. So with more draw more heat, more heat on the fets the bec cant cool down as much as before, end result: overheating.

Just a possibility.

[nathanschmoekel]

I also believe that the bec in the esc is the cause and that an external bec will fix you.

The heating didn't get you when running a brushless system because the internals of the ESC are optimized for that and the brushless motor was more efficient, which allowed the bec to disapate the excess heat. The brushed motor pulls just a little more power and the esc/bec just can't shed the extra heat.

This I don't know for sure, but the path that the power follows through the ESC between the two modes (brushed and B-less) may have something to do with it....you use one less wire with brushed, perhaps there is also one section of heatsink that is also unused in brushed mode???

[Twisted Nuts]

Thanks for the responces i'm gonna try a BEC and see where that leads me.