SPEED restrictions on the M90 between Dunfermline and Kelty will be raised.
It comes after police issued a reminder to motorists that the temporary limit - in place to protect workers while upgrades are carried out on the stretch - is enforceable.
A 30mph restriction has been signposted since May 7, but that is now set to change to 50mph as work on the central belt moves into its next stage.
The initial phase resulted in the barrier having less containment than it now does.
A spokesperson for Amey, the firm who manage the motorway on behalf of Transport Scotland, said: "As we move into the next phase of the works programme, a temporary speed limit of 50mph will now apply outwith working hours on the site between 6.30am and 7.30pm.
"This reduced speed limit is required due to temporary barriers with a lower level of containment than the permanent installation being in place to protect the works area during the daytime.
"To ensure worker safety a temporary 30mph speed restriction will still apply during site working hours overnight between 7.30pm to 6.30am.
"We would urge drivers to follow the speed restrictions and be respectful of other road users, and thank them for their patience whilst these essential works are progressed."
Police had "stopped a number of drivers" after they exceeded the speed limit through the works.
A statement said: "Just a reminder that the 30mph signs on the M90 between Dunfermline and Kelty in both directions are enforceable.
"It protects the workforce and drivers as repairs are carried out.
"Fife Road Police have already stopped a number of drivers for speeding."
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