Flywheel nut won't loosen, Motor keeps spinning
 

Hi, I have a bent crank and possibly bent flywheel. How do I get the flywheel bolt off so I can insert the special tool? I'm sure i'm missing something obvious. Whenever i loosen the bolt the crank just turns.

Use an impact gun....

Or put it in gear and have someone hold the rear wheel or the bike if its on the ground.

that sounds about right

Some soft rope in the spark plug hole works as well if the valves are all closed.