I agree with Rick, I think you have a '55 bike with a '54 motor. Let us know if your dash plate (the metal plate the handlebars are bolted to) have curved sides or straight sides.
Send me a PM with your real name, the state you live in, and your bikes condition & your plans for it. I'll add you to the Simplex registry.
Wilkommen & Froheh Weinachten!!!
Mike Sal