back wheel

Can't find any information here on having two hub motors? I read they are popular but not much information online. 250w both front and back. Maybe even two 350w. Did find a guy on YouTube with dual 350w over volted and looked brilliant running off one battery. Anyone built one? Guess you could...

Hey, I`m converting a carrera vulcan 20" frame 27.5 wheels, the ebike back wheel fitted in easily into the dropouts, however when I tighten the wheel with the nuts, it almost wont move,if i loosen the nuts the wheel becomes free and rotates again...... any ideas please? I had one washer on the...