If you’re new to cycling or commuting by bike, the chances are, your change from four wheels to two will come up in conversation. Whether it’s with your colleagues who are taking an interest in your new bike, or the mechanic at your local bike shop, you’re going to want to know what you’re talking about (or at least sound like you do). This guide will give you the details of the parts of a bike and describe what they do.
Parts of a Bike: Frame, Forks and Headset
Firstly, Frame and forks, these form the solid basis of your bike. Your frame can be made out of a variety of materials such as steel, aluminium, titanium and carbon fibre. Each material has its own pros and cons depending on the function of the bike. Similarly, forks also vary depending on the function of the bike. Road bikes tend to have stiff, lighweight, rigid carbon fibre forks, where as mountain bikes have suspension forks made from various materials.
Between the frame of forks is the headset. This little device has sets of bearings that sit between the frame and forks and allow your handlebars to turn. They come in different shapes and sizes, on road bikes they tend to be internal headsets, seated within the frame and out of sight for better aesthetics and improved aerodynamics.
Parts of a Bike: Groupset
The gears and the brakes on your bike are what’s known as the groupset.
The biggest part of the groups is usually the chainset. The chain is made up from the crack arms, the chain rings and are attached to the bottom bracket. The bottom bracket is the set of bearings that sit within (or sometimes on the outside) of your frame and allow the chainset to spin.
Similarly to the two or three chainrings at the front, your bike may have a number of sprockets on the rear wheel. The number varies but can be as many as 11. All of the sprockets together are called the cassette.
To move the chain across the chainrings front derailleur, this mechanism pushes the chain either up or down the chainrings at the front of the bike. Similarly, the rear derailleur shifts the chain across the sprockets of the cassette on your rear wheel.
To make all of this happen and within easy reach of your handlebars, you have the gear levels. Depending on your type of bike these can be very different, road bikes have gear levers integrated to the brake levers, mountain bikes can have index or twist grip shifters.
Your braking arrangement will be made up of brake levers, brake callipers along with cables and hoses. Brakes vary between the different types of bikes, from lightweight cable operated callipers on a road bike to the shape stopping power provided by hydraulic disc brakes on a mountain bike.
As the name implies the chain is a linked metal chain, but these are not one size fits all and vary from groupset manufacturer and also with the number of sprockets on your cassette.
Parts of a Bike: Wheels
As both the main rotating component of your bike and also your contact point with the ground, your wheels can be an important factor to your speed on the bike. Your wheels themselves are made up of rims, spokes, nipples, hubs and skewers. Wheels come in a variety of sizes, for instance, there are multiple sizes for mountain bikes, the most common three are 26”, 27.5” and 29”. So you should know your sizes before buying tyres and tubes. If in doubt your local bike should be able to help.
If you want to commute as fast as possible, you should match your tyres to the terrain of your commute. Using chunky mountain bike tyres on the road really increases your rolling resistance and slows you down. Even if you have a mountain bike, switching to some slicker tyres you will really notice the increase in speed on the road.
Another consideration for speed is reducing the weight of your wheels. The wheels are usually considered the best area to save weight for an increase in speed. This is due to the wheels being a rotating component of your bike and so the lighter they are the less energy is required to get them spinning faster which in turn improves your acceleration.
Parts of a Bike: Finishing Kit
Last but not least is the bikes finishing kit. By finishing kit we mean the bikes saddle, seat post, seat post clamp, stem, handlebar, grips and pedals. The finishing kit on bikes often forms part of how a bike looks, but the function of these components is much more than just visual. The saddle, grips and pedals are contact points between you and your bike. The feel of the contact points is personal to you ,so there’s no right or wrong answer to these components but they do factor into your comfort of the bike.
The huge variety of pedals on the market can be quite daunting to someone new to cycling. Depending on your style of riding and how confident you are you can choose from basic flat pedals to toe clips and straps or clipless pedals which attached to cycling shoes through cleat release system. Securing your feet to the pedals does give you a more efficient pedal stroke but does have its drawbacks.
The seat post, clamp, handlebar and stem all feature in the setup of your riding position on the bike and again have an impact on how comfortable you are. The length and width of the stem and handlebars also impact on the how the bike handles.