CYCLISTS should be limited to a speed limit of 20 km/h in the city to improve safety, according to the head of Melbourne City Council's planning committee.

Councillor Ken Ong said bikes could be the ''silent killers'' in the CBD and a separate speed limit would send a signal to cyclists to slow down on the handful of streets they share with about 800,000 people on weekdays.

St Kilda Road, which is the most dangerous road in Melbourne for cyclists. Credit:Pat Scala

Cr Ong said he was almost struck by a cyclist moving at speed recently. ''The other day when I walked out from town hall I nearly got run over from a cyclist who shot through a red light as I was crossing Little Collins Street right in front of town hall.''

The councillor's call for a separate cyclist speed limit came in the same week Melbourne City Council said it would work towards introducing a blanket 40 km/h speed limit for all vehicles in the CBD.