Originally Posted by
simplygib
Although they don't publish exact numbers, Schwalbe puts the Marathon and Marathon Plus in the same category regarding rolling resistance.
Note Schwalbe, like all tire makers, uses a steel drum to measure rolling resistance. This results in flawed results. In the real world the road surface is not perfectly smooth and therefore tires which score well on the steel drum test often don't work as well in the real world. The Pluses are definitely in that category.