carrera vulcan

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...

Hi first time posting just looking for some advice . We bought a carrera vulcan espec nearly 3 years ago. Is barley been used got less than 100 miles on it. Recently it developed an E42 fault. Took it back to halfords as no one elese would touch it! Long story short needs a new motor all in...