A wild brawl has erupted on a Melbourne train after a man complained of bikes blocking the seats.

Video shared to Instagram last night shows a bald man, who appeared to be intoxicated, yelling at a group of young people surrounded by rentable oBikes on a train.

A witness has told 9NEWS the victim and his group of teenage mates were subjected to a 20-minute barrage of abuse from the vile commuter on the Hurstbridge line train.

Video of the incident was shared to Instagram. (9NEWS)

It's believed the confrontation was sparked over bikes blocking seats. (9NEWS)

The friends were on the city bound train to spend the evening playing mini-golf, when a member of the targeted group claims the man in his 40s appeared took issue with the teens.

"What happens when the train has to hit the brakes real quick…and that bike goes flying," the man can be heard saying.

"Next stop, get the f---ers off the train," he adds.

The brawl erupted about 6pm yesterday. (9NEWS)

Frustrated by the tirade, the victim made the mistake of confronting the aggressor.

A fight then breaks out, with more people yelling as one of the bike-toting passengers, dressed in a blue hood, approaches the man.

The older man then throws repeated punches at the younger male before shouting: "Disrespectful f---ing people".

Restrained against the train doors, the fired up basher continued to spit abuse.

Transport Minister Lisa Neville has condemned the behaviour, saying it doesn’t have a place on public transit.

"We don’t want to see this sort of behaviour whether it’s on our streets or on public transport,” Ms Neville said.

"It's why we’ve got protective services officers."

Metro Trains is now investigating.