Side rode next to Interstate 35/80 in western suburb of Des Moines, Iowa. South off Hickman Road to resturants. 35 mph winds through new car lots then over a small hump bridge. As you come over the bridge the speed limit drops to 25mph, but it is too late to slow, as the cop with the speed gun clocks you coming down off the bridge. The speed limit changes back to 35mph 50 yards further on, and there is no reason for the speed drop except to gather revenue for the city of Clive. No warnings are given and the cop is rude, and looking for an excuse to fine you further, so LOOK OUT!.