Asebo Pass

Overview

Asebo Pass is a Category 2 climb in Japan, running 5 km from a start elevation of 146 m to a summit of 474 m. The net elevation gain is 328 m, which puts the average gradient at 6.52% — a sustained mid-tier climb that sits firmly in the "hard but rideable at tempo" range for most riders.

The number worth watching is the gap between net elevation gain and total ascent. You gain 328 m of altitude, but you actually climb 362 m over the course of the road — 34 m more. That surplus comes from short descents and dips that you have to re-climb. In practice it means the climb undulates rather than rising in one clean line, so your legs pay for more vertical than the summit elevation alone suggests, and the rhythm resets more than once.

How the Gradient Unfolds

The 6.52% average is a blend, not a constant. With 34 m of re-climbing folded into the profile, the road clearly rises, eases, and rises again — and the steepest pitch hits 14.49%, more than double the average. Wherever that ramp sits, it will be well steeper than what your average-based expectations prepared you for.

• Flatter or gently descending recovery sections where the grade drops well below 6.52% — use them, don't coast them away.
• Repeated short rises that re-climb the 34 m of undulation, each one breaking your cadence.
• A steepest ramp near 14.49% — the single hardest effort of the climb, likely short but sharp.

Pacing Notes

On a climb this lumpy, chasing an even speed will wreck you: holding the same km/h up a 14.49% ramp demands a spike far above what you can repeat. Pace to even effort instead. Anchor your climb to your sustainable power output and let your speed fall on the steep pitches and rise on the flatter recovery sections. Over 5 km with real gradient swings, that discipline is the difference between arriving at 474 m with something left and blowing up on the first steep ramp. If you don't know your ceiling, run the FTP estimator before you go, then ride the steep sections just under it.

Gearing

The 14.49% maximum is what dictates your setup, not the 6.52% average. Come with a compact (34-tooth inner ring) or a sub-compact, paired with a wide-range cassette — a 34×32 or 34×34 low gear keeps your cadence up when the road kicks toward 14.49%. Grinding a too-tall gear on that ramp turns a manageable Category 2 climb into a survival effort. Check your chainring and cassette before the ride; the summit is a bad place to discover you're over-geared.

Summary

• Length: 5 km
• Average gradient: 6.52%
• Maximum gradient: 14.49%
• Net elevation gain: 328 m
• Total ascent: 362 m
• Category: 2

Asebo Pass is a 5 km Category 2 climb whose 6.52% average understates its true character. Pace to effort, gear for the 14.49% ramp, and respect the 34 m of undulation, and the climb to 474 m rewards a smart ride.