The critical slope is 13-15% where walking becomes more efficient than #cycling.
This is almost always for recreational cyclists. Basically, when you are able to cycle up the the hill it's more efficient.
Walking Vs Biking Uphill | Pedal Chile |
Road cycling: The "critical slope" or the incline where walking (or running) becomes more efficient than cycling is 13β15% (recreational cyclists) Mountain Biking: The βcritical slopeβ is 8 - 11% before it becomes more efficient to walk then to continue pedaling.