Fonzie was originally not allowed to wear his leather jacket

The Fonz was only allowed to wear a leather jacket because he could get hurt riding a motorcycle without one.

Winkler shared on the ABC special, 'The Happy Days of Garry Marshall' that "Garry went to ABC and he said, 'Ya know? He could be hurt if he's riding a motorcycle and he falls off and he's not wearing leather. He could be scraped.'"