The delay in putting forward a solution to the high number of bike crashes along the inner-city thoroughfare has aggrieved cycling advocates, who've campaigned for years for safer bike lanes there.

Melbourne's grand boulevard is also one of the city's most treacherous for cyclists. According to VicRoads crash data, there were 122 crashes involving cyclists – many of them doorings – and 74 involving pedestrians between 2011 and 2015.

St Kilda Road is also one of the busiest cycling corridors into the CBD, with about 3000 people riding along it each day. It is also used by 41,000 motorists and 200,000 tram passengers.

Hopes of a safety fix were raised when the government launched a study 18 months ago into the feasibility of putting 5.2-kilometre separated bike lanes between Linlithgow Avenue and Carlisle Street in St Kilda.

A proposed design for the bike lanes was due to be revealed late last year but has been delayed for an unknown period of time, and the study has been extended so further modelling can be done on the lanes' potential impact on car and truck traffic.

An aerial view of St Kilda Road. 

Roads Minister Luke Donnellan told an audience at the Bike Futures conference this month that the lanes would have to wait until the final site for Domain underground station, part of the $10.9 billion Melbourne Metro rail tunnel, was known.

"We are dedicated to putting separated bike lanes on St Kilda Road but we don't want to actually finalise design and then [the] Melbourne Metro [Authority] comes along comes along and says, we need that space, start again," he said.

Traffic flow along St Kilda Road will be heavily affected, with long-term lane closures, while Domain station is built directly underneath the road.   

Melbourne Metro tunnel works begin on leafy St Kilda Road. Photo: Paul Jeffers

Mr Donnellan told the conference he also did not want the bike lanes to disadvantage motorists and feed the sense that Melbourne's roads are a contested space between cars and bikes.

"The last thing I want to do is end up in conflict, so that we end up being seen in the community as trading bikes for cars and cars for bikes and so forth. I want to accommodate both," Mr Donnellan said.

His comments are reminiscent of remarks made by Treasurer Tim Pallas 10 years ago, when as roads minister in the former Bracks government he stepped in to block a council plan to put separated bike lanes on St Kilda Road.

The government would not say on Sunday when it would put forward a proposal for St Kilda Road.

A spokesman for Mr Donnellan said: "We want to get this right, and ensure we strike the right balance for everybody who uses St Kilda Road."

Latrobe Street is among the first in Melbourne's CBD to get dedicated bike lanes. Photo: Jesse Marlow

Bicycle Network chief executive Craig Richards said it was disappointing that "progress has stalled on the development of separated bike lanes", because the current unsafe lanes put too many people off riding.

"While St Kilda Road is one of the busiest bike routes in Melbourne, it is the domain of the strong and fearless and one of the most crash-prone routes," Mr Richards said.

"At its current state you would really have to ask yourself, would I want my 12-year-old child riding on St Kilda Road?"

The Age believes the study has weighed up a range of possible designs including Copenhagen lanes on the left-hand side of the road and a path in the boulevard's median.

Improving safety for pedestrians is also a crucial aspect of the study, which has been funded by a $305,000 TAC grant.