People who exceed the limit will get 3 penalty points.
Motorists are being advised about a new speed camera which will come into operation next week.
A 'Motorway Average Speed Safety Camera' will be in place in Co. Tipperary.
The camera monitor the average speed of a vehicle between two points, with an €80 fine and 3 penalty points for those exceeding the limit.
Although there's been a similar camera in place in the Dublin Port Tunnel, it's the first time one will be deployed on an Irish motorway.
Motoring and Transport Commentator Conor Faughnan isn't sure it will work:

Five Hospitalised After Arson Attack In Finglas
Gardaí Warn Drivers After 150 Caught Drink or Drug Driving Over Christmas Period
An Garda Síochána Release Image of Getaway Car Found Burnt Out In Naas Used In Fatal Offaly House Fire
Pedestrian Dies After Collision On R445 Monasterevin Road Outside Kildare Town
Fine Gael TD Calls For Restricted Bin Collection Times To Ease Traffic Delays
Gardaí Continue Their Road Traffic Enforcement Operation Throughout The Christmas Period
New Quality Mark To Be Introduced To Crack Down On Bogus English Language Schools
Concerns Rise As Organ Transplant Operations Decline