If you've just bought a new bike, you've probably noticed all the gears that come with it. You may now find yourself wondering, "How do I use them?" In this article, I'll provide an overview of how to use your gears to maximize enjoyment and performance while cycling. First, we’ll need to cover some background information on what gears are and why they work the way we do. Like a great road ride, this will take a meandering route to some unexpected places - we’ll cover some background information from topics as diverse as physics and physiology along the way before putting that knowledge to use with tips and strategies for using your gears.

While the background information might be complex, I can promise that with the knowledge this article will provide, using your gears won’t be. With the right context and tips and tricks, the gears on a bicycle are an extremely elegant, efficient, and helpful system that makes riding easier and more enjoyable.

Why Do Bikes Have Gears?

In simple terms, gears change the ratio of pedal strokes to wheel revolutions. Big gears rotate the wheels more distance for each pedal stroke, while small gears cover less distance for each pedal stroke.

Using a range of gears allows cyclists to ride comfortably at different speeds. Pedaling a large gear will cause the bike to go fast, while a small gear will cause the bike to go slowly. This seems extremely simple but is incredibly powerful when on the road. A few simple gear shifts can allow you to comfortably ride up steep climbs and power down fast flat roads.

If you’re still trying to wrap your head around gears, we often use the metaphor of shifting gears in a car. If you remember using a manual transmission, you’ll know that you use first gear for low-speed driving, second gear for faster driving, and higher and higher gears for higher speeds. Cars have multiple gears so the engine can work most efficiently at different speeds. The same principle applies on a bike, except the rider is the engine! We want to use low gears for low speeds, like steep climbing, and high gears for high speeds, like flat and downhill riding.

An essential component of changing gears is to allow riders to spin their legs at a comfortable cadence (cycling term for revolutions per minute of the pedals) on all types of terrain. Cyclists use gears to maintain an ideal cadence of 80-100 RPM. You can count your own cadence by keeping track of how many times one leg pedals in a minute. You can also count the number of pedal strokes in 15 seconds and multiply by 4. While it might seem simpler to push the pedals harder at a lower cadence, “spinning” at a high cadence puts less strain on your muscles and puts more of a burden on your aerobic system. You’ll be able to ride longer and more efficiently by spinning, as well as reduce the strain on and chance of injury to your joints.

Gear Basics and Drivetrain Anatomy

Gearset Components

The front and rear derailleurs, chain, and cassette are vital elements in the bike's gear system. The derailleurs are responsible for shifting the chain between gears. The front derailleur moves the chain between the front chainrings, while the rear derailleur shifts the chain across the cogs on the cassette. These components are crucial for smooth gear transitions and maintaining an efficient pedaling cadence across various terrains.

Drivetrain Overview

Gears are part of a bicycle drivetrain, which fittingly consists of all the components that drive the bike forward. These include:

• Shifters: mounted to the handlebars and used to select gears
• Crankset: located at the bottom bracket, uses pedals to rotate the chain forward
• Chainrings: 1-3 large rings on the crankset
• Chain: connects the crankset and rear wheel
• Front derailleur: shifts between front chainrings
• Cassette: 8-13 small cogs at the rear wheel
• Rear derailleur: shifts between cogs on the cassette

Chainrings

Chainrings are located at the crankset. Most road bikes have two chainrings (referred to as a double or 2x setup), while many modern mountain and gravel bikes have just one chainring (referred to as a 1x setup). Hybrid bicycles can have anywhere from one to three chainrings (called a triple or 3x setup).

Chainrings are quite straightforward - the bigger the chainring, the bigger the gear and faster it will propel the bike. On conventional 2x road setups, the large outer chainring is used for flat, downhill, and high-speed riding, while the smaller inner ring is used for climbing and lower speed riding.

Many modern road bikes are specced with compact chainrings with something like a 50/34 combination. This number means the larger ring has 50 teeth while the smaller ring has 34 teeth. Compared to older chainrings, compacts are easier to maintain a high cadence on while climbing. Larger chainrings are still available, such as 54/39 combos, but those are mostly used by professionals and serious racers.

Cassettes

The cassette is the cluster of cogs on the rear wheel. It consists of 8-13 cogs arranged from largest diameter to smallest diameter.

Confusingly, while larger chainrings represent harder gears, larger cogs on the cassette are actually easier gears. This inversion is due to the difference between mechanical forces at the pedals and wheels. A good way to cut through the confusion is to remember that for both the chainrings and cassette inboard gears (closer to the wheel and crankset) are always easier, while outboard gears (those further away from the wheel and crankset) are always harder.

Cassettes are named in two ways. First, the number of cogs refers to the speeds of the cassette as well as the entire drivetrain. Second, the cassette is described by the number of teeth and lowest and highest gears, such as 10-32T. So, I could say I have a 12-speed 10-32T cassette. The bigger the largest cog, the easier it will be to pedal uphill. Modern road bikes are often equipped with 32T or 34T cogs, while mountain bikes can have a massive 52T cog for easy climbing. While larger cogs make things easier, it’s important to remember that not all derailleurs are compatible with larger cogs.

Note: Because absolutely nothing in the bike industry is simple or consistent, the word Speeds is used differently for different types of bikes. For most road, gravel, and mountain bikes, speeds refers to the number of cogs on the cassette. If there’s a double crankset and eleven-cog cassette, the bike might have 22 total speeds, but it would be referred to as an eleven-speed bike.

For many fitness and hybrid bikes, companies use the total number of speeds to describe the bike. A basic hybrid bike might have a triple crankset and seven-cog cassette but would most often be marketed as a 21-speed. Confusing!

Correctly Changing Gears

If you’ve made it this far, thank you and congratulations. It’s not the easiest material to pick up, but I think a solid understanding of the what and why behind drivetrains and gearing makes it much easier to understand the how of using your gears on the road.

Changing gears is actually fairly straightforward (especially in comparison to what we just learned!) but there are a few general rules and specific things you’ll want to avoid.

1. Shift when pedaling

The front and rear derailleurs rely on chain tension to properly shift. If you’re coasting and trying to shift, the chain can drop (come off the chainrings). To avoid this, make sure you’re pedaling forward when you shift up or down. You’ll also want to avoid smashing through several shifts at once, which causes the chain to drop. It’s better to shift sequentially, giving the derailleur time to move the chain through each gear.

2. But don’t pedal too hard!

Derailleurs are temperamental machines. They’re extremely reliable as long as they’re treated right. One thing they despise is shifting under load, such as when pedaling standing up on a steep climb or starting from a dead stop. To avoid this, try to select the right gear before climbing or reduce the pressure on the pedals slightly if you need to shift.

3. Use the Rear Derailleur Often

Most shifts should use the rear derailleur, which has more gears to choose from. Intermediate and advanced cyclists will shift thousands of times per ride, constantly switching gears to match the terrain to their speed and cadence. Shifting the rear derailleur provides the small steps needed to efficiently match your cadence to the terrain.

4. Use the Front Derailleur Sparingly

It is recommended to shift the front derailleur when significant changes in gradient or speed are needed. For example, when you reach the top of a hill, shift to the big chainring to gain speed on the downhill. A useful guideline is to use the rear derailleur to fine-tune your cadence, and the front derailleur for significant changes in speed or power.

5. Don’t Cross-Chain

Cross-chaining is a major no-no in shifting. It occurs whenever you use the innermost chainring and outermost cog of the cassette or vice versa. There’s no good reason to do this - It’s inefficient and the same gear combinations are available with a shift of the front derailleur.

Cross-chaining causes excess wear on the drivetrain and is quite noisy. If your chain seems especially loud, take a look down and see if you’re cross-chained. No shame - it happens to even the most experienced cyclists - but you’ll want to adjust your gears to get the chain back to a relatively straight chainline.

You can avoid cross-chaining by synchronizing front and rear shifts. If you’re in a small gear but planning to shift into the large front chainring, begin with a few downshifts of the rear derailleur to put the chain onto a middle cog. If you’re going from a steep downhill into a climb, downshift a few times at the rear cassette before shifting into the small front chainring. This will help keep your chainline straighter, reduce wear, and lessen the chance of chain drops.

6. Practice!

At the risk of stating the obvious, the single best way to get more comfortable shifting gears on your bike is to spend time shifting gears on your bike. It’s a great idea to find a quiet stretch of bike path, road, or parking lot where you can practice operating your shifters and make sure you’re comfortable up- and down-shifting.

If you’re new to the sport or this is your first new bike in a while, feel free to look down at the drivetrain to see what happens when you operate the shifters. Eventually, this will become second nature and you’ll develop an innate sense of when to shift and where the chain is in the gears, but it takes time and dedicated practice to develop these skills!

Types of Shifters

Continuing our theme of complexity over simplicity, different styles of bikes utilize different shifters to operate their drivetrains. We’ll cover each of the most common types found on different styles of bikes but it’s hard to write hard and fast rules for how to use each type of shifter since there are variations of type and between different brands. The best advice I can give is to plug your model of shifter into YouTube and check out a video on operation, and make sure to practice, practice, practice!

Drop Bar Bikes

Modern drop bar bikes, like those used for road and gravel riding, almost exclusively use STI-style shifters.

STI Shifters / Brifters

In the 1990s, Shimano revolutionized shifters with the introduction of the Shimano Total Integration (STI) Shifter, which integrated the shifter into the brake levers.Today, these types of levers are referred to as “STI” or “Brifters” (brake + shifters) and are produced by all major manufacturers.

STI shifters usually use the brake lever as well as one additional lever to up and down shift. Typically, the left brifter operates the front derailleur while the right derailleur operates the rear derailleur.

Flat Bar Bikes

Flat bar bikes include mountain bikes, hybrids, and fitness bikes. There are two main types of shifters you’ll find on these styles of bikes.

Trigger Shifters

These are the most common type of shifter, particularly for high-end mountain bikes. Trigger shifters are essentially levers that you push shift the chain on the front and rear gears. There are usually two levers per shifter, one each for up and downshifting. Bikes with a 1x setup have just a single right-hand shifter, while bikes with multiple front chainrings will have a left-hand shifter as well.

Grip Shifters

These are typically found on older mountain bikes and lower-end hybrids and allow the rider to change gears by twisting the grip on the handlebars. Many grip shifters have indicators that show which gear you are in. However, trigger shifters are generally faster and more accurate, making them the preferred choice for mountain bikers over grip shifters.

Final Thoughts

I hope this article has provided solid background information on the why and how gears on a bike are used. We’ve covered the basics of how gears allow riders to maintain a comfortable cadence in different types of terrain as well as how to identify and name different parts of a bike drivetrain. While this is a lot of information, it should make a lot of sense the next time you’re out for a ride and you look down at your drivetrain as you shift while climbing and descending.

The shifting tips and things to avoid provided above are all you need to know for simple and effective use of your gears. Again, it’s important to take the time to familiarize yourself with your own bike’s components and practice shifting. With practice, I have no doubt you’ll be finding the perfect gear on the road in no time!