BikeScout Encyclopedia | S-Scale: Technical Trail Grading
Description: Mastering the S-Scale (Singletrail-Skala): How BikeScout classifies trail difficulty from S0 to S5 using technical OSM metadata.
Keywords: S-Scale, Singletrail-Skala, MTB Difficulty, Trail Grading, Technical Terrain, BikeScout Encyclopedia, hifly81

# S-Scale
Trail Grading

Core Concept: Technical Difficulty Standards

In off-road exploration, distance and elevation only tell half the story. The S-Scale (Singletrail-Skala) is the international benchmark used by BikeScout to quantify the technical demand of a trail. By parsing OpenStreetMap (OSM) tags, we assign a grade from S0 to S5 to help riders determine if a mission matches their skill level and equipment.

## Standard Classification

BikeScout's `_analyze_technical_difficulty` module maps raw metadata into six distinct levels of technicality:

Grade | Description | Typical Obstacles
--- | --- | ---
S0 | Easy / Flow | Smooth, firm soil, no obstacles.
S1 | Intermediate | Small roots, loose stones, easy water bars.
S2 | Advanced | Larger roots/stones, steps, shallow switchbacks.
S3 | Technical | Rock gardens, high steps, tight hairpins.
S4 | Extreme | Steep ramps, switchbacks requiring trial skills.
S5 | Near Vertical | Maximum difficulty, high risk of falling.

## The Visibility Factor

Technicality isn't just about rocks; it's about pathfinding. BikeScout integrates Trail Visibility metadata into the tactical briefing. This is critical for missions in volcanic or high-alpine environments where the trail can become "Invisible" (Visibility Level 4), requiring GPS-only navigation.

## Strategic Deployment

The S-Scale grading directly influences the ASI (Actionable Setup Intelligence). If BikeScout detects an S3+ segment, it will automatically trigger a "Compliance Strategy" for tire pressure, even if the rest of the route is smooth. Furthermore, for Road profiles, any segment graded above S will trigger a critical safety warning.

"Knowing the difficulty before the first descent is the difference between a scout and a survivor."

#MTB-Scale #Technical-Grading #OSM-Intelligence