RCU Forums - View Single Post - E-flite 400 size 3700 kv bruchless in e-flite Ascent...
Old 07-11-2005, 08:05 AM
  #2  
Matt Kirsch
My Feedback: (21)
 
Matt Kirsch's Avatar
 
Join Date: Jul 2002
Location: Spencerport, NY
Posts: 7,350
Likes: 0
Received 0 Likes on 0 Posts
Default RE: E-flite 400 size 3700 kv bruchless in e-flite Ascent...

What battery are you using?

You need to be careful here. Direct drive, this motor won't be able to spin a very large prop without drawing too many Amps and burning up. A 6x3 might give you phenomenal performance, but it may not last very long.

I just ran the numbers on P-Calc at www.flydma.com, and on a 7-cell NiMH pack, that motor is drawing 38 Amps... Too much. If you fly it like that, you'll get ONE flight.

Don't fall for the "bigger motor means more power" trap. As you've found out, that's usually completely opposite of what happens. See, bigger motors are designed to handle higher voltages, so if you don't compensate for that, you end up with LESS power and more weight. The smaller 400 is actually more powerful than the larger 480 in this case because the 400 motor is designed to run on a lower voltage than the 480. Since you didn't increase the voltage to take advantage of the 480 motor, it wasn't turning enough RPMs to pull the plane.