Originally Posted by
CMUidiot
Thanks for the good info. So if I'm using a lipo that's a 5000 mah with an older ESC, would it be safe to assume a 20 minute runtime without discharging the battery to a harmful stage?
No, never assume.
Depends on the motor you are using and the RC, and how and where you drive, etc. Too many variables. A heavy RC with a hot motor with lots of gearing, no way. Lighter RC, stock motor with moderate gearing, maybe.
Note in general a brushed setup will use more power for the same speed, it’s considerably less efficient than brushless.
Stock 27T motor, maybe start with 10 minutes top, hotter modified, perhaps 5 minutes or less, better safe than…. be sure to track the time. Then a couple ways to check: Check the at rest voltage, this you can do sorta on the fly. You don’t want it lower than 3.7V per cell at rest for best lipo life. Or recharge and note the amount put back in, stay below 80%, or 4000mAh in the case you mention. Then work your way up accordingly, but remain aware of variables that might increase power drain, and leave a cushion.
Even with a modern ESC with a cut off/LVC feature, stop as soon as it seems to drop off in power. Use the LVC as a back up only, it will help with cycle life.