Col du Pin Bouchain

What the Col du Pin Bouchain Is Like to Ride

The Col du Pin Bouchain is a Category 3 climb in France, running 8.6 km from base to summit. On paper, a 3.55% average gradient reads as manageable — the kind of number that tempts riders into an optimistic early pace. Don't be fooled. The total ascent across the climb is 540 m against a net elevation gain of 307 m, which tells you the road is not a straight ramp. That gap between total ascent and net gain signals meaningful elevation variation along the route: the gradient is distributed unevenly, with flatter or even slightly descending sections masking where the real effort is concentrated.

The maximum gradient of 18.71% is the headline stat that demands respect. A pitch approaching 19% is not a passing inconvenience — it's a section where even well-trained climbers will be at or near their functional threshold power for a sustained effort if they haven't managed their energy carefully on the lower slopes.

How the Gradient Unfolds

With an average of 3.55% over 8.6 km and a maximum of 18.71%, the climb is clearly not uniform. The arithmetic confirms it: to average under 4% across the full distance while still hitting nearly 19% somewhere on the road, there must be extended sections of low single-digit or flat gradient. This produces a rhythm-breaking profile — long stretches where you can push a bigger gear and recover, punctuated by sharp, steep ramps that demand a rapid shift in effort and cadence.

The start elevation of 451 m and summit at 758 m establish the overall context: this is a mid-altitude climb, not a high-mountain sufferfest, but the steepest pitches will spike heart rate and burn through glycogen quickly if you arrive at them too fast.

Pacing Notes

The uneven gradient profile makes even pacing by perceived effort dangerous here. Riders who treat the shallow sections as recovery and use them to spin up cadence will arrive at the steep ramp in far better condition than those who hammer the flats trying to bank time.

• On the easier sections: Settle into a sustainable cadence. Keep power at or below threshold. Use these stretches to eat, drink, and lower heart rate.
• Approaching the steep ramp: Shift to a smaller gear before the gradient kicks up. Trying to change gear mid-ramp at 18%+ wastes momentum and risks a chain issue.
• On the 18.71% maximum pitch: Expect to drop cadence unless you are running a compact chainset or a wide-range cassette. If your lowest gear can't hold 70–75 rpm at that gradient without exceeding your FTP, you will be out of the saddle and burning matches. Consider your gearing before the ride, not during it.
• Post-ramp: If the steep section appears before the summit, don't sprint out of it — there may still be climbing left and your legs will have taken a hit.

Gearing Recommendation

For most amateur riders targeting a controlled effort, a compact crankset (50/34) paired with an 11-32 or 11-34 cassette is appropriate. The 18.71% maximum gradient on a 34×32 gives a gear ratio that keeps most riders turning the pedals rather than grinding. Riders on standard cranksets should ensure their cassette runs to at least 28t, and should plan for standing efforts on the steepest pitch.

Use the FTP estimator to benchmark your watts per kilogram before attempting this climb at race pace — the steep sections will expose any gap between your threshold and your ambition quickly.

Summary

The Col du Pin Bouchain is a Cat 3 climb that rewards patience and punishes complacency. Its 3.55% average is soft enough that many riders underestimate it, but the 18.71% maximum gradient and 540 m of total ascent demand a disciplined approach. Ride the easy sections easy, gear down early for the steep pitch, and don't let the low average number set your tempo.