Gear Ratio Basics: Why Top Riders Are Also Using Lighter Gears, and How to Think About Climbing Wuling

Starting from a Common Misunderstanding

In Taiwan’s cycling community, “using a lighter gear ratio” is often seen as a sign of weakness. Before climbing Wuling, if someone says they’re going to swap on a larger cassette, chances are someone nearby will joke, “Not enough leg power, huh?”

But looking at trends in the pro peloton, you’ll find that the opposite is true: more and more top riders are choosing lighter gear ratios on ultra-steep climbing stages. Riders from Tadej Pogačar’s generation use a much wider gear range on climbs with double-digit gradients in Grand Tours than their predecessors did twenty years ago.

The reason is simple, and it has nothing to do with willpower: Gear ratio isn’t about proving how strong you are—it’s about keeping you in your most efficient cadence.

What Gear Ratio Actually Is

The definition of gear ratio is very straightforward:

Gear ratio = Chainring teeth ÷ Cassette teeth

• Large gear ratio (e.g., big ring up front, small cog in back): each pedal stroke covers more distance, but each stroke is heavier → harder gear
• Small gear ratio (e.g., small ring up front, large cog in back): each pedal stroke covers less distance, but each stroke is lighter → easier gear

Multiply that by the tire’s rolling circumference, and you get the “distance traveled per pedal stroke”; multiply that distance by your cadence (rpm), and you get your speed:

Distance per pedal stroke = Gear ratio × Tire rolling circumference
Speed ≈ Distance per pedal stroke × Cadence

These formulas are the entirety of the math behind gear ratios—no mysticism involved. The table below is a purely conceptual illustration; the values are just mathematical examples and don’t correspond to any specific product:

Why “Lighter Gears” Are Actually an Efficiency Choice

1. Cadence That’s Too Low Comes at a High Cost

When the gradient gets steep enough to force your cadence very low, several things happen:

• Force per pedal stroke increases, raising muscular tension load; fast-twitch muscle fibers get heavily recruited, and fatigue accumulates faster.
• Knee joint stress rises—this is one of the most common sources of injury from prolonged low-cadence grinding.
• Pedaling becomes discontinuous, speed fluctuates between each stroke, and the bike rocks and becomes harder to balance.
• Once you lose speed, it’s very hard to recover, because there’s no easier gear left to drop into.

In other words, low-cadence grinding isn’t “more manly”—it’s pushing yourself into a zone with no way out.

2. Gear Reserve Means Pacing Flexibility

Success on a long climb almost always comes down to pacing. If you’re already in your easiest gear at the start of the climb, then when the gradient steepens or you start to fatigue, the only adjustments left are slowing down or stopping.

Keeping one or two easier gears in reserve is like keeping strategic options open. That’s also why pro teams tend to spec wider gear ranges on steep stages.

3. Weather and Unexpected Conditions

Taiwan’s mountain routes often bring low temperatures, strong winds, and rain. A headwind on a climb is effectively a steeper gradient—and in that situation, having one extra easy gear can be the difference between “making it through” and “walking the bike.”

How to Think About This for a Wuling Challenge

First, the most important point: The correct gear ratio depends on your ability, body weight, luggage load, and conditions on the day—no one can give you a guaranteed set of numbers from behind a screen. What follows is a method, not an answer.

Method 1: Self-Test with “Can You Hold Your Target Cadence on the Steepest Section?”

Find a climb with a gradient close to the steepest part of your target route that you can sustain for several minutes (for example, the steep sections of Fengguizui or Beiyi). Using the same bike and gearing you plan to take up Wuling, hold a cadence you can sustain steadily for a long time in your easiest gear.

• If you can hold it steadily and your breathing stays manageable → your current gearing is probably adequate.
• If you have to stand up and grind, or your cadence drops to a point where every stroke feels like a struggle → strongly consider widening your gear range.

Remember to factor in fatigue. The steep sections of Wuling often come after you’ve already been riding for hours, so results from testing in a “fresh state” tend to be overly optimistic.

Method 2: Factor in Supplies, Luggage, and Clothing

On a long climb, you’ll be carrying water, food, a windbreaker, and tools. The impact of that weight on steep climbs is real, so try to simulate your actual load as closely as possible during testing.

Things to Confirm Before Changing Your Gearing

Gearing isn’t something you just swap without thinking. Please verify the following first (and if you’re unsure, go straight to a trusted bike shop):

1. Rear derailleur capacity and maximum cog size: Exceeding the design limit can cause poor shifting or even the derailleur hitting the wheel.
2. Chain length: Going to a larger cassette usually means recalculating and extending the chain.
3. System compatibility: Different brands, generations, and mechanical vs. electronic shifting have different pairing restrictions.
4. Extreme gear combinations: Avoid prolonged use of combinations like big chainring with big cassette, where the chain angle becomes too extreme.

In general, expanding the cassette range is lower-cost and simpler to do; changing the chainrings involves more compatibility concerns.

Two Reminders on Mindset

• A lighter gear doesn’t mean riding slower. It lets you output at the same power with a more suitable cadence. Many people find that after switching to a wider gear range, their overall climb time improves and recovery the next day is faster.
• Don’t ignore your body’s signals in pursuit of numbers. Knee discomfort, tight hips, or cramping while pedaling are all signals that your gearing or riding position needs adjustment; train progressively, as individual differences are large.

Summary

Pro riders choose lighter gears not because they’ve gotten weaker, but because they know better than anyone: on long, high-intensity climbs, maintaining an efficient cadence matters far more than toughing it out.

For riders preparing to take on Wuling, what you’re fighting isn’t just the gradient—it’s also time, cold, wind, and the version of yourself that’s deep in fatigue.

Save some gear reserve for the rider you’ll be later—that’s usually the person on the road who needs help the most.

This article is a conceptual explanation, not individualized advice. For actual gear selection and component compatibility, please consult a professional bike shop; for training and challenges, progress gradually according to your personal condition, and stop immediately if your body feels unwell.

Related Reading

• Gear Selection for Climbing Races: Chainring and Cassette Setup Advice Before the Event
• Gear Ratio Selection Strategy: When to Switch to a Compact Crank? A Decision Matrix of Gradient and Heart Rate
• When to Shift on a Climb: A Complete Guide to Bicycle Gear Selection
• Mountain Gearing Strategy: Shifting Techniques and Gear Choices for Different Gradients