Col de Moi

Overview

Col de Moi is a hors catégorie (HC) climb — the top rung of the difficulty ladder, above categories 1, 2, 3 and 4. Over 13.3 km it lifts you from 169 m at the base to a 1233 m summit, a net gain of 1064 m. The average gradient of 7.98% barely tells the story: this is a long, sustained effort where the road rarely relents, and where a single peak of 20.68% waits to expose anyone who started too hard. With 1049 m of total ascent packed into those 13.3 km, there is almost no flat road to recover on — nearly every metre climbed is a metre you keep.

How the Gradient Unfolds

A 7.98% average across 13.3 km means the climb sits, on the whole, in that punishing 7–8% band where you can neither spin easily nor stand and power away for long. The gap between the 7.98% average and the 20.68% max is the number to respect: that 12.7-percentage-point spread signals ramps that spike well above what your legs are calibrated to. Expect the gradient to breathe — pitches that ease toward the average, then steepen sharply — rather than a smooth, even wall. The near-equal net gain (1064 m) and total ascent (1049 m) confirm there is essentially no descending or false-flat relief; what goes up stays up, all the way to 1233 m.

Pacing Notes

On an HC climb this long, discipline beats bravado. Anchor your effort to your FTP: for most riders, a sustainable climbing effort sits just below threshold, and 13.3 km at 7.98% is long enough that going over early will cost you dearly on the upper slopes. If you don't have a recent number, run the FTP estimator first and set a ceiling you can hold for the full duration. Treat the 20.68% max as a moment to survive, not attack — shift down early, keep your cadence from collapsing, and let the pitch pass before you settle back to rhythm. Bank nothing in the first few kilometres that you'll want back before the 1233 m summit.

Gearing

With an 7.98% average and spikes to 20.68%, gear for the steepest ramp, not the average. A compact 34-tooth inner paired with a wide-range cassette is the sensible baseline. A 34×32 will get many trained riders up the sustained sections, but on the 20.68% pitch — 13.3 km into the effort, with 1064 m already in your legs — that ratio can leave you grinding below a survivable cadence. If you have any doubt about your climbing legs or your load, fit a 34×34: the extra sprocket buys you cadence exactly where the gradient tries to take it away. On a climb this relentless, easier gearing is not weakness; it is what keeps you pedalling to the top.

Summary

Col de Moi is a true HC ascent: long, steep, and unforgiving, with no flat to hide on and a max ramp that demands respect. Pace to your threshold, gear generously, and the 1233 m summit is yours.

Length: 13.3 km
Average gradient: 7.98%
Max gradient: 20.68%
Start: 169 m
Summit: 1233 m
Net gain: 1064 m
Total ascent: 1049 m
Category: HC