Nice motor Matrix1000;
It would help alot if you could estimate the voltage it is reaching at any given RPM, so others could give a more accurate answer. If you don't have a lathe, you might Hammer a wood crank on that shaft, watch a stop watch closely, and crank it at one crank a second (60rpm) or two cranks a second (120rpm) and see what the voltage is. Or what I do is duct tape a 3/8" bolt to the shaft of the motor and chuck it in a big slow 600rpm drill and see what voltage it reaches. My quess, (&I'm no expert) would be a 5' diameter set of blades. The 6.5' might work--- or it may go to slow of rpm to reach the motors best generating potential. Its difficult to estimate without knowing a voltage reading at any given RPM. Does the motor cog that bad?
