[trebuchet03]

Originally Posted by basjoos

Concrete pavement is the best, followed by smooth asphalt, gravel asphalt, brick/cobblestone, gravel, no pavement (grass, dirt, mud, sand, etc.). Your mileage losses on bumpy surfaces is caused by the energy lost by the movements of the suspension system.

I'm willing to bet grooved concrete doesn't fare as well (perhaps between smooth asphalt and gravel asphalt).... The noise itself is an indicator of energy losses....