On flat terrain, gradeability is a footnote in the specification sheet. On a mountain scenic route it becomes the specification that decides whether a vehicle can operate at all — and whether it can do so safely when fully loaded.
A 25% grade means the road rises 25 metres for every 100 metres travelled horizontally — roughly 14 degrees. That is steep: many mountain scenic roads include sections in the 15–25% range, and wet or gravel surfaces raise the effective difficulty further.
Torque delivery — electric motors deliver maximum torque from standstill, which is an advantage, but the controller and gear ratio must be matched to the grade, not only to top speed.
Energy cost — a steep section can consume several times the energy per kilometre of the flat sections around it. Underestimating gradeability requirements often shows up later as unexpected range shortfall.
Safety margin — climbing ability is specified at full load. A vehicle rated for a 20% grade with a full passenger load is not suitable for a 25% section, even if it manages the climb unloaded.
| Terrain | Typical maximum grade | Vehicle gradeability to specify |
|---|---|---|
| Flat scenic paths, parks, campuses | Under 10% | 15–20% |
| Hilly resorts, undulating park roads | 10–20% | 20% |
| Mountain routes, steep access roads | 20–25% | 25% at full load |
DAOD sightseeing and shuttle models are commonly specified with 20% or 25% gradeability; the correct choice depends on your steepest sustained section, not the average gradient of the route.
Measure the steepest continuous section, not the steepest single point.
Check surface condition — wet paving, gravel and loose surfaces reduce usable traction.
Confirm the gradeability figure is stated at full passenger load.
Ask about regenerative braking behaviour on long descents; it affects both safety and energy recovery.
Share your route's steepest section and typical load, and we will confirm which configuration is appropriate — or propose a mixed fleet for flat and mountain sections. Contact DAOD for a terrain assessment.
