Kobotoke Pass

Overview

Kobotoke Pass is a Category 2 climb in Japan that runs 6 km from base to summit. It starts at 171 m and tops out at 618 m, delivering 447 m of net elevation gain across its length. On paper that reads as a steady mid-length effort, and the 7.47% average gradient places it firmly in serious-climb territory.

The number that reframes the ride is total ascent: 554 m against 447 m of net gain. That 107 m gap is undulation — vertical you climb, give back, and climb again. It means the pass is not a single clean drag but a rolling profile with descents and false flats woven in. Expect to change rhythm repeatedly, and expect the legs to register more work than the net figure suggests.

How the Gradient Unfolds

The 7.47% average is a blend, not a constant. With 107 m of descent folded into the route, the climbing sections must be steeper than the average to compensate for the metres you lose on the dips. Ramps will bite harder than the headline number implies, and the recovery you get is real but short-lived.

• Flatter and downhill sections where you can breathe, roll, and reset cadence
• Repeated short climbs stacked back to back rather than one continuous wall
• The steepest ramp will feel well above 7.47% — save something for it

Pacing Notes

On a clean climb you pace to even effort. On an undulating one like Kobotoke, even effort and even speed diverge sharply: hold steady power through the dips and you will coast fast on the descents but need to surge on the pitches. Anchor your effort to your sustainable power output and let speed float — push a touch above threshold on the steep ramps, ease back on the flatter recovery sections, and never chase a fixed pace over the rollers. Know your ceiling before you start; the FTP estimator gives you the number to pace against so you do not blow up on the first steep section.

Gearing

Gearing is dictated by the steepest ramps, not the average. On a 7.47% climb with pitches that run well steeper, run a compact (50/34) or sub-compact chainset paired with a wide-range cassette — a 34×32 or 34×34 low gear keeps cadence up when the road kicks. Under-gearing here forces you to grind at low RPM and drains the legs before the summit. Check your setup before the ride; swapping a cassette at the trailhead is not an option.

Summary

• Length: 6 km
• Average gradient: 7.47%
• Net elevation gain: 447 m
• Total ascent: 554 m
• Category: 2

Kobotoke Pass rewards riders who respect the undulation. Pace to power, gear for the steep ramps, and treat the 554 m of total ascent — not the 447 m net — as the real measure of the day.