You are in your easiest gear, halfway up the steep hill that always decides how the ride ends.
Your legs are barely turning.
We usually blame our legs, our fitness, or the day we are having. Sometimes, though, it really is the bike.
Years ago, I tried riding up a steep climb of about 12% on what was then a fairly new road bike, with a compact crank and an 11-26 cassette. I literally couldn’t turn the pedals, and I wasn’t anywhere near as fit as I am now.
I quickly learned I needed easier gears and swapped to an 11-30 cassette straight away. It made a huge difference.
You may not need a new bike at all. The gears your bike came with might be the problem, not your legs.
So start with the numbers already on your bike, check them against your hills, and price the cheapest fix before you do anything drastic.
What The Numbers On Your Gears Mean
If you have never looked at the tiny numbers stamped on your gears, you’re not alone.
The chainrings are the toothed rings the pedals turn, usually two on a road bike. The cassette is the cluster of cogs on the rear wheel.
A cog is one of the toothed rings in the cassette, and the tooth count is simply how many teeth it has.
Tooth counts are usually stamped right on the metal. A compact crank often reads 50T and 34T, and a cassette is named by its smallest and largest cogs, like 11-32.
Shimano’s 105 crankset is sold as 50-34, 52-36 and 53-39, with the 50-34 as the compact.
The easiest way to compare gears is to divide the front teeth by the rear teeth. When the small 34T ring meets a 34T cog, the ratio is 34 divided by 34, exactly 1.00.
Cyclists call that 1:1. One full pedal turn turns the rear wheel once.
On a typical road wheel, with the wheel and tire about 27 inches across, 34/34 sends you about 7.1 feet per pedal turn. A 34/28 gear covers about 8.6 feet, and a 30/34 about 6.2 feet.
Smaller number, shorter push, easier climb.
This table shows what those combinations feel like as the road tilts.
| Gear (front/rear) | Ratio | Distance per pedal turn | How it feels |
|---|---|---|---|
| 50/11 | 4.55 | About 32 ft | Big push for fast flats and descents |
| 34/28 | 1.21 | About 8.6 ft | Steady effort on gentle hills |
| 34/32 | 1.06 | About 7.5 ft | Easier push on longer moderate climbs |
| 34/34 | 1.00 (1:1) | About 7.1 ft | Light push up steep sections |
| 34/36 | 0.94 | About 6.7 ft | Very light push for sustained steep climbing |
| 30/34 | 0.88 | About 6.2 ft | Easiest here, for the steepest pitches |
Find the row that matches your easiest gear.
The combination that matters most is your easiest gear: the smallest front ring paired with the largest rear cog.
Take a stock bike such as the Trek Domane AL 2 Gen 4. It ships with a 50/34 crankset and an 11-32 cassette, so its easiest gear is 34/32, a ratio of 1.06.
That is just a little harder than 1:1.
👍 Luckily, bikes today are generally sold new with a much wider range of gears.
Still, check yours rather than assuming. The numbers sit on the chainrings and the largest rear cog, or on the bike’s spec page.
How To Tell If Your Gears Are Too Hard
Look for these signs on your next climb:
- You are already in the easiest gear before the steep part begins.
- Your legs turn so slowly that you are close to stalling.
- You stand up just to keep the pedals moving, not because you chose to.
- You weave across the lane or stop.
As a rough example, a rider and bike weighing about 198 lb (90 kg) holding about 150 watts on an 8% grade moves at roughly 4.5 mph with no wind.
At that speed, a 34/28 gear means only about 46 rpm. A 34/34 raises that to about 56 rpm, and a 30/34 to about 63 rpm.
Easier gears are not about becoming a high-cadence spinner. Sacchetti and colleagues, in a 2010 lab study, tested competitive cyclists averaging over 65 years old and found they were most efficient at the low end of the tested cadences (40 rpm, not different from 60 rpm).
They also lost efficiency more steeply than younger riders as cadence rose, and in a maximal test they freely chose lower cadences.
That is a small lab study of steady moderate efforts. Still, it shows why easier gears help: they give you the choice of a cadence you can hold seated instead of being forced down into the 40s.
You don’t need a magic number. Find your own cadence and match your gears to it.
Easier gears also cut the force on each pedal stroke. At the same power and speed, moving from 34/28 to 34/34 raises cadence about 21% and cuts the force on each stroke by about 18%.
💡 For me, having easier gears put much less stress on my knees.
If the climb feels like you are mashing a big gear rather than riding it, your gearing may be the problem.
And if the bike feels hard everywhere, not just on hills, check the simple stuff first.
Fix One: A Bigger Cassette
🔧 Either a bigger cassette or smaller chainrings will do the job, but the cassette swap alone is much cheaper. It also depends on where you plan to ride and what you actually have now.
Before you buy a bigger cassette, check the rear derailleur, the arm that moves the chain across the cassette. Each derailleur has a limit on the biggest rear cog it can reach.
- Find the model name, usually marked on the derailleur body.
- Look up that model’s biggest cog.
- Pick a cassette within that limit.
The Shimano 105 RD-R7000-GS medium cage 11-speed road derailleur handles up to a 34-tooth cog.
| Shimano rear derailleur | Speeds | Biggest rear cog |
|---|---|---|
| 105 short cage (RD-R7000-SS) | 11 | 30T |
| 105 medium cage (RD-R7000-GS) | 11 | 34T |
| 105 (RD-R7100) | 12 | 36T |
| Ultegra medium cage (RD-R8000-GS) | 11 | 34T |
| Sora (RD-R3000-GS) | 9 | 34T |
| Claris (RD-R2000-GS) | 8 | 34T |
Other brands and models have their own limits, so look up yours before you buy.
There is a second limit called capacity. It is how much spare chain the derailleur can take up across all your gears.
It equals big ring minus small ring, plus biggest cog minus smallest cog. A 50/34 crank with an 11-34 cassette needs 16 plus 23, or 39, exactly the limit of the 105 medium cage.
A shop can run this sum for you.
The cassette must match your speeds: 8, 9, 10, 11 or 12. Some cassettes fit the wheel differently, like Shimano’s 11-speed 11-34 (CS-HG800-11). Ask a shop to confirm it fits your wheel before you order.
A bigger cog usually means a longer chain too. We have a separate guide for sizing a bike chain if you do this at home.
In round numbers, a 10-speed 11-34 cassette such as the Shimano CS-HG500-10 runs up to about $65. The 11-speed 11-34 CS-HG800-11 is about $100 to $150.
Prices vary, so treat those as a starting point.
Fix Two: Smaller Chainrings
If your hills are long, or your derailleur is already at its limit, look at the rings your pedals turn.
Sub-compact cranks such as a 48/32 or a Shimano GRX 46/30 drop the small ring from a compact crank’s 34 teeth down to 32 or 30 teeth. The 30T ring makes the low gear about 12% easier.
A 30T ring with a 34-tooth cog gives a ratio of 0.88, comfortably below 1:1.
A 46/30 crank with an 11-34 cassette needs 16 plus 23, or 39 teeth of capacity, the same as a 50/34 with an 11-34.
Shimano makes the GRX 46/30 in an 11-speed version (FC-RX600-11) and a 12-speed version (FC-RX610-2).
The tradeoff is cost and fit. A Shimano GRX FC-RX600-11 46/30 crankset runs about $165 at one US retailer, against about $65 to $150 for a cassette.
Don’t assume a gravel crank drops straight onto a road front derailleur. Have a shop check the fit before you hand over money.
When Your Derailleur Is The Limit
If your derailleur can’t reach the cog you want, there are three ways round it.
- Short cage to medium cage: on 11-speed Shimano 105, swapping the short cage (30T limit) for the medium cage (34T limit) lets you fit an 11-34.
- Past 34T on 11-speed: a hanger extender such as the Wolf Tooth RoadLink ($23.95) lets a 10- or 11-speed road derailleur reach up to a 40T cog. It adds no capacity, needs a medium cage derailleur if you have two chainrings, and doesn’t suit triples or frames built for direct-mount derailleurs.
- 36T the factory way: Shimano’s 12-speed 105 (RD-R7100) takes up to 36T. But it’s a 12-speed part, so it also means 12-speed shifters, chain and cassette, and a wheel that takes Shimano’s 12-speed road cassette. That’s a bigger job, and a shop job.
DIY Or Shop, And What It Costs
The parts are one cost. The labor is another, and sometimes the wiser spend.
⚠️ If you’re new to cycling, it’s probably best to take it to a shop to get this done. The chain will also likely need replacing.
The table below uses approximate US prices and one shop’s menu from Cartersville, Georgia.
| Fix | Parts (approx. USD) | One shop’s labor |
|---|---|---|
| Bigger cassette | $65-150 | $15, plus $15 chain install |
| Smaller chainrings | About $165 GRX 46/30 | $35 crankset install |
| Hanger extension | $23.95 | $30 derailleur install and adjust |
Prices move: one US retailer listed the 11-speed 11-34 at $99.99 on sale against a $149.06 list price. The same Georgia shop charges $90 an hour for work not on its menu.
To size a new chain for cogs of 36 teeth or smaller, wrap the chain around the largest chainring and largest cog, skipping the derailleur. Find the closest joining rivet, then add two rivets (one inch).
After any swap, shift through every gear.
In the biggest ring and biggest cog, the chain should not be stretched tight. In the smallest ring and smallest cog, it should not sag.
If You Ride A Hybrid
Hybrid riders may already have climbing gears.
The Trek FX 2 Gen 4, for example, pairs a 40T front ring with an 11-46 cassette. That gives a low ratio of about 0.87, already easier than 1:1.
That bike uses a Shimano CUES 9-speed rear derailleur and a LINKGLIDE 11-46 cassette.
If your hybrid already has gears like that, the next fix is how you climb, not a part.
The First Check To Make Before Your Next Hilly Ride
You can settle this before you buy anything.
🚴 My easiest gear right now is 34/32, although I’m planning on getting a 34/36. I can never say no to easier gears.
If the fear of steep hills still stops you from joining a ride, there is also a calmer way through.
Your next step is to read your three numbers: the small ring, the largest cog, and the derailleur model.
Write them down, then price the cassette that fits your derailleur. Change the gearing before the bike.
Know a riding buddy who fights the same hill? Share this below👇
