I have been flying powered planes and gliders for several years and just got started in electrics.
I have a Great Planes Electrostreak and never tried the supplied motor. I have a Wattage Super 05 cobalt geared motor with 10 1500 mah and a Jeti 500 speed controller. When I check my power output with an Astro Whattmeter, I get 34 amps but only 7.5- 8 volts. Is this normal? It seems that 10 x 1.2v should = 12v. Do I have an abnormal amount of resistance between the battery and the motor?

What type batteries are you using? Some cannot take 30+ amps and will complain. Check out the solder connections at the connectors, by the way, what type connectors are you using?? anderson powerpoles, astro, graupner and new dean 2 pin are the best..the car taymara(?) type ia a no-no and should be cut off and replaced.

Hope this helps,

Jarvis