Billy Smith, 26, saw the victim stood outside a block of flats in Woodston, Peterborough, in May 2018.
He marched towards the victim, who was loading his belongings into the under-seat storage of his moped, and demanded to be let into the building.
The victim refused, saying he didn’t have his keys with him, sparking Smith into a fit of rage.
He grabbed the victim’s helmet and struck him twice in the face, once in the back and once in the chest.
Smith, of Lake Court, Wisbech, then stormed towards the building and forced his way through the doors, as onlookers saw the stricken victim bleeding heavily from the mouth.
He returned five minutes later from the building and approached the victim for a second time – on this occasion shouting he was going to come back later that evening and steal his moped.
Police arrived and searched the area. The ensuing investigation eventually led to Smith’s arrest for assault occasioning actual bodily harm several months later.
Last week on Monday, August 17, at Cambridge Crown Court, he was jailed for a year and handed a restraining order to prevent him from contacting the victim.
DC Fran Scott said: “This violent, unprovoked attack has resulted in a great deal of physical and emotional trauma for the victim.
“I hope this sentence will give Smith sufficient time to re-think his actions, and he will restrain himself from lashing out again in future.”