I picked up a brushless outrunner ($5) at a flea market. It is rated 11.1V 6.5A. As all of my flying has been with 7.4V 2s LiPo was wondering what effect on the amps will using it with 7.4V have ? Don't want to burn out my ESC. Also looked at a 350mAh 2s 7.4V LiPo pack that had a 4lead balancing tap (1 black and 3 red) I didn't buy it, I have been led to believe that a 2s pack would only have a three lead balancing tap. Thanks in advance for the help on this.
slowgo

You might get an answer by asking the same question in the Electric forum.

CGr

Battery voltage determines the speed that the motor will run at. A motor intended for 11.1 volts will run at about 2/3 the speed if you reduce to 7.4 volts (assuming no load).

The current the motor draws will depend on the size of prop you put on it. The motor will try and spin up to its no-load speed, with a small prop this will take less current as the work done will be less.

This is the short version!

Terry

Any motor you can have for $5 is probably worth even less.

There are some people who just don't know what things are worth, but it would be wrong to take advantage of an idiot. What you likely bought was a five-dollar chinese brushless motor which will work just fine. It will be very ineficient, a bit heavy, lack power and likely break within fewer than 100 flights.

The UP-side is that you can get a motor that will work in some really cheap planes for $5. As has been stated, you can expect much less performance from that motor at 7.4V. And truly, IMHO, anything with such a small amount of power should be flown indoors, or on a windless day.