Drivers angered by a sudden drop to the Westway speed limit have been told it is only a temporary measure while repairs to the elevated section are carried out.
Motorists – including Top Gear presenter Jeremy Clarkson – raised concern this week that the reduction from 50mph to 30mph might be a permanent measure, and slammed Transport for London for failing to explain the move.
But TfL has revealed that the reduced limit was imposed in mid-February due to issues with ageing expansion joints on the raised part of the Westway at White City, which has now been patched up to allow for more substantial repairs.
Resident Virginia Ironside, of Loftus Road in Shepherd's Bush, said the sudden drop to 30mph was a 'mystery'.
"It is officially a motorway after all, and a 30mph motorway is a baffling event," she said.
"If one were told a reason for the reduction, everyone would pay attention, but just to impose such a drastic reduction like that is irritating."
Blogger Martin Lewis used his moneysavingexpert.com website to question whether the reduced speed limit might have made the road less safe for motorists, particularly those on scooters.
He said: "As a frequent scooter rider, it’s virtually impossible to stick to the speed limit. If I go 30mph everyone is on my tail or beeping dangerously, as the road is naturally much faster, and people simply haven’t adapted to the new speed limit. There are no speed cameras on the road, so most people still go at the old limit, leaving it tough to stick to the new one."
It is not yet known how many weeks or months the 30mph limit is likely to be in place, but a TfL spokesman said it may be possible to raise it again while works are still ongoing.
He said: "TfL has temporarily reduced the speed limit from 50 to 30 mph on the A40 Westway while we carry out bridge maintenance to replace several of the expansion joints on the flyover. The work will be done as quickly as possible with the minimum amount of disruption.
"New road markings have been painted onto the carriageway as this section of the A40 is not currently lit at night. The speed limit has been reduced to 30mph to keep the road open."
Signs had to be painted on the road because they could not be attached to the narrow hard shoulders, he said, and there is no power supply to the raised section. The lower speed limit is necessary to preserve the temporary repairs.