The Sandymount cycleway is now due to begin a trial on 15 January after an alternative plan put forward by residents was rejected by the National Transport Authority.
The trial proposed by Dublin City Council will involve a dedicated two-way cycleway on the road with general traffic confined to one lane outbound from the city centre.
This would have involved using the seaside footpath as the cycleway and cyclists would merge with traffic at bus stops.
However a briefing for councillors heard that the National Transport Authority had rejected the plan as the footpath is not wide enough.
It also stated that the proposal for cyclists to merge with traffic at bus stops by going around buses would pose a safety risk and force traffic to stop.
It also said the plan would involve engineering works such as the removal of lamp posts and other street furniture on the footpath.
Local Independent Councillor Mannix Flynn said local residents will be disappointed but said the council should now work with them to find a solution acceptable to all.
There will be a residents' forum held later this month and the cycleway is due to go ahead in January for a six-month trial.