Big Hole Pass cycling climb profile
Big Hole Pass is a category 2 climb in the US that asks for patience more than aggression. The headline number is manageable - 24.6 km at an average gradient of 3.82% - but that average is spread across a long ascent from 1212 m to 2152 m. The net elevation gain is 940 m, which means the climb is not a short power test. It is a sustained aerobic effort where early overpacing can quietly become expensive.
The key detail is the gap between the average gradient and the maximum gradient of 10.68%. A climb averaging under 4% can look benign on paper, but a double-digit maximum tells you the road has sharper moments embedded inside the larger drag. That changes how it should be ridden. The mistake is treating the whole climb like a fast false flat and then arriving at the steeper ramps already above your sustainable ceiling.
How the gradient unfolds
From bottom to summit, the climb gains height steadily enough to produce nearly a kilometre of net elevation gain, but the average gradient suggests the resistance is usually controlled rather than relentlessly steep. The challenge is duration. Over 24.6 km, even a moderate gradient becomes a real load because there is so much time under pressure.
The 10.68% maximum gradient is the tactical warning sign. Without specific sector data, the safest reading is that Big Hole Pass is not a uniform metronome climb. Expect the effort to fluctuate. Some portions will ride closer to steady endurance climbing, while the steepest pitch will demand either a short lift in power or a deliberate reduction in speed. The rider who keeps the early kilometres smooth will have more room to absorb those changes.
Pacing strategy
Ride this as a long controlled climb, not as a threshold test from the base. The average gradient is low enough that speed can be tempting, especially early, but the full 24.6 km length makes restraint the higher-percentage choice.
Practical pacing notes:
- Start below your target climbing effort and let the climb come to you.
- Keep power or perceived exertion stable across the easier gradients instead of chasing speed.
- Save a gear and some torque capacity for the 10.68% maximum pitch.
- If using power, anchor the climb around sustainable aerobic output rather than repeatedly punching above /glossary/ftp.
- In the final portion, only lift the effort if breathing and cadence are still under control.
Gearing notes
Because the average gradient is 3.82%, Big Hole Pass does not require a pure wall-climb setup for most riders. But the maximum gradient of 10.68% means the easiest gear still matters. A cassette that lets you keep cadence stable on steep ramps is more useful than a tighter range that feels efficient only on the moderate sections.
The best setup is one that lets you ride the bulk of the climb seated and relaxed, then stay seated or smoothly stand through the steepest pitch without grinding. On a climb this long, cadence preservation is fatigue management. Once cadence collapses, the effort shifts from aerobic control toward muscular strain, and that is exactly what turns a category 2 climb from steady to costly.