The 19-year-old was branded a ‘professional thief’ by a judge after hearing he also stole 10 bikes from the area.
Portsmouth Crown Court heard the male victim, who is under 18, saw the bike advertised on Gumtree, a classifieds website, and went to get it.
The victim met Wild and his co-defendant Chelsea Hales, at the car park at Tesco in Fratton Way, Portsmouth, on January 16.
Simon Foster, prosecuting, said the boy said he wanted to test it out after paying the £100 in cash.
Mr Foster said Wild, who admitted robbery, then got on the bike and a struggle started that attracted passers-by.
Mr Foster said: ‘The defendant told them this was a drug transaction. He did tell them to call the police.
‘The tussle over the bike continued. The defendant said “let go of the bike or I’m going to punch you”.’
Wild then punched the victim three times in the face and Hales got on the bike and rode off, Mr Foster said.
In a victim statement read out in court, the boy said he was left with a sore jaw.
During the hearing, it was revealed Wild had previously stolen 10 bikes from Horizon Leisure Centre in Havant, Petersfield train station, Cunningham Road Waterlooville, Petersfield Community Hospital and other addresses in Petersfield.
The court heard on one occasion he took a bike from a nursery after going there enquiring about a place for his child.
Wild has 19 previous offences, the court heard.
Sentencing, judge Roger Hetherington jailed Wild for two years and six months.
Addressing Wild he said: ‘He wanted his £100 back and the response he got from you was to be punched hard three times in the face on the jaw, lip and nose.’
He added: ‘As far as the thefts are concerned, they were professional thefts.’
Each bike was worth around £400 on average.
Wild, of Fourth Street, Fratton, breached a conditional discharge for possessing cannabis. He was found guilty of nine thefts for 10 bikes in September and October last year by city magistrates.
Hales, 18, of Fourth Street, Fratton, was given a community order with curfew at a previous hearing after admitting robbery, the court heard.
The judge said she had a lesser role in the robbery.