The Singletrack Scale comprises six difficulty ratings, ranging from S0 - S5. The difficulty rating of your Tours is graded according to this scale. The difficulties are graded based on the consitution of the trail, the types of obstacles present, the gradient, the type of and angle of curves and — therefore — the technical skills required to safely pass.
Trails void of or with few difficulties. Mostly wider paths comprising compacted gravel or solid earth. Roots, rocks and uneven ground is not to be expected.
Trails comprising mostly compacted gravel or solid earth with some flat roots and smaller rocks. The surface may become loose at times and periods of stand-up riding may be required to overcome obstacles.
Trails that comprise a looser surface, as well as many roots and rocks. Narrow curves and steeper gradients are to be expected. Readyness to brake at all times is required, as is the ability to shift your center of gravity on the bike.
Trails that include blocked singletracks, hairpin turns and tricky traverses. Loose scree and slippery terrain comprise the majority of the trail. Good command of the bike, excellent balance, unbroken concentration and controlled braking skills required.
Very steep and physically demanding sections of trail. Demanding root passages and very loose scree is to be expected. Exceptional riding skills are required, such as the ability to independently maneuver the front and back wheels, as well as perfect braking technique and balance. Only extremely experienced mountain bikers should attempt S4 trails.
Incredibly demanding trails that very few attempt. Expect seriously tight hairpin bends, blocked terrain, scree slopes, jumps and extreme steepness. Little to no braking time demands exceptional bike control. You will likely have to push/carry your bike at numerous points, although the steepness of certain sections may render this incredibly difficult.