Police clocked more than 140 drivers breaking the speed limit in just over three hours on roads around Horbury and Ossett.
Following concerns from residents, they took a laser gun to 30mph zones on Bridge Road, Benton Hill and Addingford Raod in Horbury, and Towngate and Queens Road in Ossett, where they spent between 25 minutes and an hour monitoring traffic on each road.
They found more vehicles driving at 36mph or more on Addingford Road and Benton Hill (18 and 17 respectively), with Towngate having the lowest number with zero. Benton Hill also had the most drivers driving between 30mph and 35mph, with 35 vehicles.
A police spokesman said: “This operation was done as an informative exercise to identify problem areas. No tickets were distributed at this time.”