A man rides into town on Friday and three days later, leaves on Friday. How does he do it?

it’s the weirdest thing I’ve ever heard
any clue?

Is his horse/bike/car named Friday?

Friday is the name of his horse.

I’m picturing Sgt. Joe Friday from Dragnet carrying him piggy-back style in and out of town, dropping him at the city line, and saying, "And stay out!

Arcidee and DrLisa are right, Friday is his horse!!