Battery/motor heat question

[tracerbob]

I fairly new to electric helis and I need some advice on how warm should the battery/motor should get during a hovering only flight. I have a mini titan 325 with the stock motor and ESC. I'm using DN power 2150 15C batteries. I've only flown this bird twice and I noticed the batteries and ESC are warm and the motor is almost hot after a flight. Is this normal? If not, what is? Thanks

[Danal Estes]

Ideal temp for LiPo is 110F at end of flight. Below 100F, they won't deliver current for hard stuff. Reasonable limit is 140F (some shortening of life at 140), absolute NEVER EXCEED is 160F, at that temp there is drastic shortening of live and/or they are teetering on the brink of a thermal runaway and fire.

Motor depends on quality of magnets. Most are OK at 100C (212F) internal; expensive or "excellent brand name" motors way above that... but it's hard to measure magnet temp. So, 180F is a reasonable limit for most motors. Cooler is always better.

[tracerbob]

Sounds like my batteries are right on line with 110deg. The motor still feels hot to the touch but not so hot that I have to let go or get burned. Thinking about switching from the 13 tooth pinion to the 11 and see what happens. Thanks!