Traffic counts by Spokes, the Lothian Cycle Campaign, on Tuesday showed 26.1 per cent of vehicles in Forrest Road, north of The Meadows, were bikes.
The figures, compiled from 8-9am, also showed cycles accounted for 22.7 per cent of traffic in Lothian Road.
Spokes said it counted more than 500 bikes for the first time since the surveys started 11 years ago.
Car numbers have declined from 1,995 to 1,617 since then, but nearly eight out of ten had only one occupant.
Spokes said segregated cycle lanes on “scary” Lothian Road could further boost cycling.
Its spokesman said: “There are few roads in the city which would benefit so strongly from such a scheme.
“There is almost certainly a big pent-up further demand from people who’d like to cycle but don’t feel safe.”