A second trial to allow motorcyclists to use some London bus lanes is to take place, after the first showed an increase in collisions.
A report into the first 18-month trial, due to end on 5 July, has shown a rise in accidents, predominantly with cars.
But the findings also showed a fall in cyclist collisions in the trial lanes and a decrease in motorcyclists' journey times.
The second 18-month trial is due to start on 16 July.
The independent report had compared the 28 trial lanes, to 28 control sites on parallel routes where motorcyclists did not have access to bus lanes.
It found an increase in the rate of motorcyclist collisions, predominantly with cars turning into or out of side roads on routes where motorcyclists had access to bus lanes.
At the trial sites there was an increase from 30 to 41 collisions, whereas there was a reduction from 16 to eight on the control sites.
Transport for London said in the light of these findings a second trial will take place which will run alongside a road safety awareness campaign aimed at improving drivers' awareness of motorbikes and cyclists in bus lanes.
Mayor of London Boris Johnson, said: "Motorcyclists have made a consistent case to be able to use TfL's bus lanes, and the initial trial has shown some positive results.
"The chaos that was predicted by some doomsayers has clearly not materialised and, as I suspected would be the case, we have found substantial support for the measure.
"There is always scope for improvement and a new trial, with a strong focus on safety, will allow motorcyclists to show that they can adhere to the spirit of the trial and ride with respect."
Motorcyclists will still be allowed to use the bus lanes between the first trial ending and second one beginning.