
Lolo Pass
A data-driven profile of Lolo Pass, an 8.4 km Category 2 climb in the US with 425 m net gain but 807 m of total ascent.
- Length
- 8.4km
- Avg
- 5.0%
- Max
- 17.4%
- Summit
- 1,613m
- Ascent
- 807m
The climb
Gradient profile
Overview
Lolo Pass is a Category 2 climb in the US, running 8.4 km from a start elevation of 1188 m to a summit at 1613 m. On paper it delivers 425 m of net elevation gain at an average gradient of 5.05% — a mid-tier ascent that most fit riders can hold at tempo without blowing up. The category and length put it in reach of anyone comfortable with a sustained 20-to-30-minute effort.
But the net figure understates the work. Against 425 m of net gain, the climb racks up 807 m of total ascent — meaning roughly 382 m of the elevation you earn is given back to descents and dips along the way, then climbed again. That undulation matters: your legs pay for every one of those 807 vertical metres, not just the 425 that show up between the base and the summit. Expect the perceived effort to run higher than a smooth 5.05% grade would suggest.
How the Gradient Unfolds
The 5.05% average is a blend, not a constant. With 382 m of regained elevation folded into the profile, the road repeatedly climbs, releases, and climbs again — and the maximum gradient hits 17.4%, well above anything the average hints at. The flat sections and short descents drag the average down, which means the climbing pitches are meaningfully steeper than 5% when you are actually on them.
- Flatter and recovery sections where the road eases or briefly drops — use them, don't coast mentally
- Repeated short climbs that stack up to the 807 m total ascent
- A steepest ramp of 17.4% that demands a low gear and a controlled cadence
Pacing Notes
On an undulating climb like this, even-speed pacing is a trap. Holding a constant speed forces you to spike power on every one of the steep ramps and soft-pedal on the flats, torching your reserves early. Instead, pace by even effort: hold a steady, sustainable output and let your speed rise on the shallow bits and fall on the 17.4% pitches.
Anchor that effort to your sustainable power output rather than to how fast the flatter sections let you go. If you don't know your number, run the FTP estimator first, then target a percentage you can hold across the full 8.4 km — including the regained metres.
Gearing
The 17.4% maximum gradient governs your gearing choice, not the 5.05% average. On a ramp that steep, an under-geared bike forces you out of the saddle and into surges you can't afford. Run a compact (50/34) or sub-compact chainset paired with a wide-range cassette — a 34×32 or 34×34 low gear gives you the room to spin the steep pitches at a sustainable cadence. Check your setup before the ride; discovering you're over-geared halfway up a 17.4% wall is not the time to find out.
Summary
- Length: 8.4 km
- Average gradient: 5.05%
- Maximum gradient: 17.4%
- Net elevation gain: 425 m
- Total ascent: 807 m
- Category: 2
Lolo Pass reads as a moderate Category 2 climb, but the gap between its 425 m net gain and 807 m total ascent is the real story. Pace by effort, gear for the 17.4% ramps, and treat it as the rolling test it is rather than the steady drag its average suggests.