On our portal downhill single tracks are classified into three grades of difficulty (easy, medium and difficult), the single-track scale (STS), which is commonly used in mountain biking and corresponds to the colour coding of ski slopes (blue, red and black). Furthermore, six additional “s‑grades” help differentiating between the individual grades. On the basis of the STS, technical difficulties of flat or downhill sections can be indicated, with the higher grades of difficulty mostly being reached by single tracks only.
The s-grades of the single-track scale
Trail section without difficult sections such as rocks, steps or roots. It takes its course over flat or moderately flat forest or meadow paths with open, wide curves.
Trail section with smaller obstacles such as small stones, rocks and gullies on earth paths with up to 40% steepness without kick turns.
Trail section with bigger stones, roots, steps and flat stairs and frequently on earth paths with up to 70% steepness and narrow curves.
Slippery single tracks across large rocks, gravel, difficult root sections, high steps and kick turns with up to 70% steepness and bevel steep ramps.
Very steep single tracks blocked by big rocks, with difficult root sections between loose gravel, high steps, extreme kick turns and steep ramps.
Extremely blocked, loose and narrow terrain with gravel fields, extreme steps, additional ascents, kick turns and numerous obstacles (such as fallen trees) in extremely steep terrain.
The most frequent grade of difficulty of a trail sections determines the general grade of the whole track.