From commuting to shopping to exercising, road bikes are used for both recreation and utility. Two factors that all road bike owners have to take into consideration are speed and ease of pedaling. Bike gears are what determine both of those factors. Making sure that you have the proper gears on your bike for your activity of choice is important to your comfort when riding your road bike.
There are many aspects of bike gears that must be understood in order to choose the right gears for your road bike. Make sure to consider:
- How many gears your road bike needs to function properly.
- The different kinds of drivetrains that you can choose from.
- How to choose the correct gears for the function you need.
- Types of gear shifters, their purpose, and how they work.
Once you’ve looked into each of the facets of bike gears and their specific benefits and shortcomings, you can confidently outfit your road bike gears to fit your individual needs.
How Many Gears Does a Road Bike Need?
Because there are many different kinds of road bikes, there are also many different kinds of gears. Each road bike has bike gears that match the performance that is expected from the bike. Typically, road bikes have at least 18 gears but can have anywhere from 1 to 30 or more gears.
- Front gears, also called chainrings and cranksets, are located in the front of the bicycle gears. Cranksets most commonly have a single chainring, double chainring, or a triple chainring, consisting of 1, 2, and 3 gears, respectively.
- Rear gears, also called cogs, are located in the back of the bicycle gears. If there are a number of rear cogs put together in ascending size, they are called a cassette. Usually, you will find 8 to 11 cogs in a cassette. The larger the cog, the lower the gear.
- Derailleurs simply move the bicycle chain from one cog or chainring to another cog or chainring when switching gears. The front derailleur moves the chain to another chainring. The rear derailleur moves the chain to another cog and also maintains the chain’s tension.
Now that you know the different parts of bike gears, you can properly determine the number of gears that your bike needs. To figure out a basic gearing system, you simply multiply the number of front chainrings by the number of rear cogs. For instance, if you have a triple chainring and a 10-speed cassette, you will have a 30-speed bicycle. Ultimately, you have thirty different gear combinations.
The Different Drivetrains You Can Choose From
The drivetrain of a bike contains all of the pieces and parts needed to make the bike move. Drivetrains include the crankset, the rear cassette, the derailleurs, the pedals, and the brake and gear levers. Since there are a variety of road bikes that are designed for different tasks and terrains, there are also many drivetrains to choose from. Often, discussions about a bike’s drivetrain leads to the gearing system.
Some basic drivetrain gear combinations are:
- Triple Crankset – 3 chainrings paired with a 9-speed cassette that results in 27 gears. It is most often found on entry-level road bikes.
- Double Crankset – 2 chainrings paired with a 10-speed cassette that results in 20 gears. It is most often found on recreation bikes.
- Compact Crankset – 2 chainrings paired with a 10-speed cassette that results in 20 gears; however, this crankset has smaller chainrings and fewer teeth than the double crankset, so it has a lower range of gears. It is most often found on performance bikes.
These are not the only drivetrains that are available. There are 5 other common types of derailleur gearing. Derailleur, or external gearing, has all its parts visible. Generally, derailleur systems consist of up to 4 chainrings that are attached to the crankset and pedals with anywhere from 5 and 11 cogs in the cassette. A chain runs around the chainrings and cassette as the pedals turn.
|Types of Derailleur (External) Drivetrains
|-Commonly found on mountain, hybrid, and touring bicycles.
-Relative step of chainrings is about twice that of the cassette.
-Provides a wide range of gears for touring and off-road cycling.
-Easier to manage gears for casual riders.
|-Commonly found on racing bikes.
-Relative step of the chainrings is about 3 or 4 times that of the cassette.
-Allows for a more constant pedaling speed.
|-Can refer to three different gear arrangements
-(original)Has one extremely low gear for cycling on Alpine passes
-(1960s) Referred to a 10-speed bike with two chainrings and a 5-cog cassette.
-(current) describes Shimano Megarange cogsets with all cogs at 15% relative difference but one, which is 30% relative different to switch to a much lower gear.
|-Used regularly in the mid-20th century.
-Relative set of the chainrings is about half that of the cassette.
-Provides two gear ranges.
|Half-Step + Granny Gearing
| -Three chainrings with half-step differences between the bigger two and multi-range differences between the smaller two.
-Good for touring bicycles.
-Small chainring is referred to as the “granny gear” and helps to bike over steep hills.
A type of internal gearing that can be used in a drivetrain is a hub gear, also called an internal-gear hub or a gear hub. With a hub gear, all the gears and pieces that move the bike are housed inside the shell of the hub, which keeps them protected from the elements, unlike the regular derailleur drivetrains.
Hub gears require less maintenance than other gears. However, they are not made to withstand high-stress conditions like competitions, hilly, and off-road cycling. Road bikes that feature hub gears are most commonly made in 7-speed and 8-speed, but there are some 3-speed and, more currently, 14-speed hub gear bikes that are available.
Some advantages of hub gears are:
- They require less maintenance because their gears are sealed within a hub.
- They are more simple to use for inexperienced cyclists.
- They avoid the danger of gear collision with the spokes and wheels of the bike.
- They are able to change gears when the rear wheel isn’t moving.
- They protect both the chain and your clothing from nasty grit and lubrication rub-off.
- They make it very hard to switch to another gear while you are pedaling.
- They are part of the rear wheel, so they must be changed when the rear wheel is changed.
- They are more expensive than derailleur systems.
- They are heavier and may affect traction and braking while cycling.
- They are less efficient than derailleur systems for commuting and recreation.
Another type of internal gearing is bottom bracket gearing. These systems have been available for use since 1890 and have their gears in the crankset or bottom bracket of the bike. With this kind of gearing, you switch gears by tapping a button that protrudes from the bottom bracket with your foot. It is good for use with mountain bikes and full-suspension bikes.
|Other Gearing Systems and Combinations
|1. 3-speed hub gear combined with a 2-speed derailleur gear, resulting in 6 gears total. This is the standard option for Brompton folding bicycles.
|2. SRAM DualDrive system. This gearing system uses an 8 or 9-speed cassette that is mounted on a 3-speed hub gear.
|3. Double or Triple chainring paired with a hub gear. This system requires a chain tensioner which takes away from the function of the hub gear.
|4. Hub gear combined with both front and rear derailleur gears, resulting in three different sets of gears and is usually used with recumbent trikes.
|5. Retro-Direct Drivetrains. With this system, you pedal forward for one gear and backward for another gear. It was used in the early 20th century, and some bicycle enthusiasts have resurrected the gearing system.
|6. Flip-Flop Hubs. This kind of gearing system is located on a double-sided rear wheel, and you have to manually remove the wheel and switch it around to change the gears.
|7. Continuously Variable Transmissions. These systems are new developments and use balls that are connected by static friction to change gears.
How to Choose the Correct Gears for Your Road Bike
Choosing the right gears for your road bike first means considering the following two factors: what kind of road bike do you have and what do you plan to do with it.
To begin, the following are general features and functions of all road bikes:
- Lightweight in construction – frame, wheels, and components
- A dropped handlebar – can be either curved or flat
- Narrow wheels and tires
- Composite front fork
- No front or rear suspensions
- Available in men’s and women’s styles and many sizes
- Often used for fitness, riding at events, and competitions
- Made for paved surfaces
- Allows the cyclist to go farther and faster than many other bikes
Within the road bike category are many different types of bikes that are specialized for certain purposes. The following chart gives details about the types of road bikes and what they are made for.
|Type of Road Bike
|Details and Descriptions
|-Designed to go fast.
-Aerodynamic low-sitting front end.
-Stiff frame but responsive handling.
-Uses higher gearing.
-Skinny, lightweight wheels. Made for high speeds and racing.
|-Can handle off-road terrain as well as paved roads.
-Designed more for rider comfort.
-Must have disc brakes.
-Strong, well-built frame.
-More solidly built than regular road bikes frames.
– Made for off-road and general riding.
|-Built to offer the speed of race bikes with added comfort to help with endurance.
-More upright riding position.
-Frame geometry is adapted for stable handling during long distances.
-Uses lower gearing to handle hills.
-Basically, a more comfortable race bike.
-Made for long distances and hilly terrain.
|-Borrows the aerodynamic features of a time trial bike and places them on a race bike frame.
-Same frame geometry of a race bike but made of carbon.
-Cables are run through the inside of the frame.
-Uses higher gearing.
-Uses deep section wheels.
-Made for speed on longer, flatter courses; mid to high speeds.
|-Made for comfort and durability.
-Upright riding position for comfort and vision in traffic. Strong wheels for longevity.
-Sturdy tires for more protection from impact and comfort. -Uses disc brakes.
-Can have either drop or flat handlebars.
-Made for daily reliability and comfort for commuting.
|-Made for long-distance comfort while carrying heavy loads.
-Uses very low gearing. Long and mostly upright frame geometry for comfort and easy handling.
-Tough wheels with more spokes than normal wheels.
-Uses disc or rim brakes. Made for touring.
|Time Trial (TT)/ Triathlon Bikes
|-Made to go as fast as possible and cheat the wind.
-Full of aerodynamic features.
-Frames have large, flat tubes, steep angles, and hidden cables and brakes.
-Frame geometry sits the cyclist low and further forward over the bottom bracket for efficiency.
-Aero bars that extend out the front.
-Uses highest gearing for speed.
– Uses deep section carbon fiber rims, tri-spokes, or disc rear wheels.
-Made for riding as fast as you can against a clock.
In essence, the most basic determinations of which gears you need for your bike is this: For speed, you need higher gears. For navigating hilly terrain, you need lower gears. However, while these determining factors are enough for most cyclists, there are more factors that can determine more specific gearing.
Other variables that can affect your choice of gears and number of gears are the following:
- Your weight, strength, and endurance
- How far you ride daily
- How much you carry on your bike
- How hard you’re able to push your pedals
- How much you’re willing to maintain your bike
To be able to ride a bike, all you need to have is one gear. All other gears will simply make your riding easier. Single-speed bikes are typically the bikes that casual riders use to ride over paved and flat roads when there is no need for special gear needs.
To customize your gear system to your personal needs, you should take into consideration the following: range and gradation, efficiency, cadence and resistance, and gear progression.
Range and Gradation
When you move into multi-speed gear set ups, you have to consider range and gradation. The range is the number of gears you are able to move through, and gradation is the series of successive changes you can make within your gears. Both of these work together to optimize your road bike gears. Nonetheless, there is usually a trade-off you have to make between the two in order to choose the best gears.
- If you have a small range, which means closely-spaced gears, you are able to fine-tune your gears when it comes to riding on level, flat surfaces; however, you may not have a high enough gear for optimal speed or a low enough gear for optimal steep terrain navigation.
- If you have a wide range, which means your gears are spaced further apart, you’ll be able to go faster and navigate steep conditions very easily; however, the gradation, or jumps between gears, may be too large to be able to find a comfortable gear for riding on flat terrain.
While it would seem that every cyclist would want efficiency, this isn’t normally the case. By definition, efficiency determines how far and fast you can go while expending the least amount of energy. Some riding purposes don’t need maximum efficiency while others do.
- Some road bike users that do not need maximum efficiency are those that ride bikes primarily for exercise, short-distance commuters, utility cyclists, trial and freestyle riders, and those who ride in short-distance, non-aerobic competitive events like BMX. For these riders, single-speed, internal-geared, or fixed-gear bikes are suitable.
- Multi-speed bikes offer more efficiency for those cyclists that need it. Some cyclists that need maximum efficiency are touring riders, commuters that have medium to long distance commutes, and long-distance racers.
Cadence and Resistance
Cadence and resistance, like range and gradation, work together. Cadence is your pedaling speed in revolutions per minute. Resistance refers to how hard you have to push your pedals in order to keep your speed. The purpose of gears is to keep your cadence and resistance steady, so you are not having to exert different levels of energy at different times, which can tire you out much faster.
- As the wind or terrain changes, you should switch gears to allow you to continue pedaling with the same cadence and resistance as before. This can cause you to lose some speed or gain some speed, but the object of the gear change is to make sure you are pedaling with the same force at the same revolutions per minute.
- According to “Gear Theory for Bicyclists” by Sheldon “Gearhead” Brown, “a good, practical [gearing] system will have as high a high as you’d want, as low a low as you’d want, and well-designed intermediate steps in a pattern that will be easy to remember and to shift.”
Gear progression refers to how your gears progress as you change them. It is important to consider how the gears are distributed and how far the gradation is for the higher and lower ranges.
- If you mainly ride on flat terrain and/or need high speeds, you will usually be using medium to high gears. Therefore, you want close jumps in your higher gears to make your riding the easiest. This is called “close on top.”
- On the other hand, “wide at the bottom” is the gear progression used for those who often navigate hilly and steeper terrain. You will use your lower gears more often; therefore, you want your closer jumps to be within your lower gears.
Types of Gear Shifters, Their Purpose, and How They Work
Drivetrains are not the only part of the gearing system that matters on your road bike. Equally as important are the gear shifters that change the gears. Gears shifters are designed to choose the gear ratio that you need, are usually used with derailleur and hub gearing systems, and are operated by cables that connect the shifter to the gearing system.
Gear shifters are generally classified into three categories:
- Dropbar Integrated Combo Shifters. These shifters are only used on road bikes that have drop-down handlebars. They are called combo shifters because both the shifter and the brake are integrated into one piece. They are lightweight and allow for easy and convenient gear shifting because of their placement. The brake lever is located in front of the gear lever, so they are still separate from each other.
- Twist Grip Shifters. These shifters are found on entry-level multi-speed bikes. The shifter is built into the handlebar’s grip on either one or both sides. It is only used in bikes that have straight handlebar styles. You shift gears by twisting your hand in either direction to go up or down.
- Thumb Shifters. Usually found on mountain bikes or hybrid bikes, these shifters are found right next to the brake levers on straight handlebar bicycles. The exact location of the thumb shifter can vary from bike to bike. Sometimes, they are on top of the handlebars, and at other times, they are on the bottom. The shifter changes gears with each click of the thumb.
The History and Evolution of Bicycles and Their Gears
Modern bicycles seem so commonplace that it’s hard to imagine them looking or working any other way. Furthermore, as complicated as bike gears are, it’s incredible to think that the first bicycles had no gears at all! The history and evolution of bicycles and their gears is rather interesting.
- The idea of the chain and the cog was developed in the 15th century by Leonardo da Vinci; however, it took 400 years for it to become practical enough to be considered for bicycle design.
- The first bicycle was called the “penny farthing.” It became popular in the 1870s and 1880s and had no chain or gears at all! The pedals were connected to the very large front wheel, and the seat sat above the front wheel.
- With the advent of bicycle chains and gears in 1885 by John Kemp Starley, “safety bicycles” were born. These bikes were referred to as such because they were much safer to ride than the penny farthings of the past because they were driven by a chain connected to the rear wheel of the bike.
- Some early bicycles required you to completely remove the rear wheel, switch it around, and reconnect it to switch to the second gear.
- Even though hundreds of gear set patents had been filed by the beginning of the 20th century, most people still used single-speed bikes because changing gears in the earliest years was very tedious and inconvenient.
- Hub gears were introduced in the early 1900s and were the dominant form of gearing system used on bicycles until around 1930.
- A French man named Jean Loubeyre patented the precursor to modern derailleur systems. His patent introduced the idea of shifting or derailing, the bike’s chain from one gear to another.
- In 1937, the Tour de France allowed derailleur gears to be used in the competition for the first time. Still, these were not modern derailleur systems, and they required the cyclists to reach down and use a level to physically change their gears – while still maintaining their balance and speed!
- In 1938, Simplex, a cycling company, introduced the first cable-shifted gear system to the biking market.
- In 1949, the Gran Sport bike was introduced by Campagnalo and featured a revolutionary derailleur design that allowed for consistent shifting with cables and pulleys. However, there was no shifter involved, and the cyclist had to go by feel to know if they were in the gear they needed.
- In the 1980s, Shimano, a Japanese cycling business, introduced “indexed shifting.” This type of shifting allowed the cyclist to press a lever and switch between gears easily.
- After index shifting was introduced, cycling changed drastically. By the early 2000s, biking speeds had almost doubled. You could ride 27-speed bicycles. Braking and shifting levers were introduced that made both actions much safer and easier to perform.
- Today, while index shifting is still the main way that gearing systems are operated on bicycles worldwide, Shimano has introduced electronic shifters that have been noticed by the hardcore cycling world. Electronic shifters move from gear to gear with incredible precision.
No matter what you plan to do with your road bike, there is a perfect gearing system for it. Remember to keep in mind that the terrain you plan on navigating plays a huge role in the gears you need – low gears for steep hills and high gears for flat or paved roads. If you know nothing else before buying your bike’s gears, you should at least be familiar with that bit of information.
The type of road bike, the drivetrain you choose, the pedals, the shifters, and the brakes on your bike make up your riding experience. Choosing the right gears for the job makes it the ultimate experience!