Cycling and bike parts glossary


Aero bike
Aero bikes are a type of bike that have oval frame and fork tubes rather than cylindrical – with the thinnest section of the frame facing forward to help make the bike cut through the air and be more aero dynamic.

As wind tunnel technology has become cheaper and more accessible to bike manufacturers aero bikes have become a more common offering. 

Aero bikes are generally more expensive than non-aero bikes, and so are only worth the investment if you are racing or doing time trials.


Barrel adjuster
Barrel adjusters are on brake callipers, levers, gear shifters and rear derailleurs. The allow the fine tuning of the cable tension to either help with indexing of gears or how close the brake pads are to the rims.

Bikepacking is a relatively new term that means strapping all the things you’ll need for multiday trips to your bike. It used to be called cycle touring, but bikepacking is the more trendy name people have adopted as they have been using gravel and mountain bikes to tackle trails and more adventurous terrain.

Bottom Bracket
The bottom bracket is a spindle and bunch of bearings that go through the bottom of the frame so the crankset can fit either side of the bike. Your pedals then fit to the crankset.

Bottom brackets used to be made up of separate pieces, but now they are self contained units. This means they aren’t serviceable, but they are really easy to replace and save you getting all messy with grease and individual bearings.


Clipless pedals
This is a confusing one, as when you are riding with clip-in pedals and cleats on your cycling shoes, you would expect these to be called clip-in pedals and everything else to be called clipless pedals.

But this goes back to time long ago, when everybody used pedals with toe clips on. It was therefore every other pedal type that was clipless, as they did not have toe clips on!

So although you clip into modern day pedals with cleats – these are actually called clipless pedals – as they do not use toeclips. 

Make sense?! 🙂

Crank Set
The crank set is made up of the front chain rings, crank arms (which is what the pedals connect to).

The cassette is the sprockets/gears on the back wheel.
All the sprockets put together is known as the cassette.

Caliper brakes
Caliper brakes work by squeezing brake pads on the rims of the bike wheels to slow it down.


Disc Brakes
Mountain bikes have been using disc brakes for years. They offer much better stopping power, especially in the wet. It took a while for them to catch on with road bikes but are generally now the preferred option.

You can get disc brake setups with either cables or hydraulic implementation. The cable setups are on more budget bikes and do not offer the same feel as hydraulic disc brakes.

Some high end road bikes still come with caliper brakes due to them being lighter and slightly more aero dynamic, but for the general sportive rider we’d recommend disc brakes.

The derailleur is the part of the bike that moves the chain up and down the sprockets on the cassette to change gears.

Di2 is Shimano’s offering on electronic shifting


Free hub
The free hub is the part on the back when that the cassette slides onto and is attached to. It’s part that makes the clicking noise when you are coasting along and not peddling.

FTP stands for functional threshold power. It is the average number of watts a cyclist can maintain for an hour, and used as a measure of fitness. 

As cyclists get fitter and stronger their FTP will increase.

It use to be a complex operation of going to a sports science lab to get yourself tested to discover your FTP, but in the days of power meters, smart trainers and Zwift anyone can easily get it worked out for themselves.


Gravel bike
Gravel bikes are a relatively new thing, and are a versatile option for people who want to ride along tracks as well as on the road. The forks and frame are wider to allow for wider off road tyres, as well as slick road tyres when you want to stick to the road.


The headset is made up of the bearings and bolts that hold the forks in place with the rest of the frame.


Jockey Wheels
The jockey wheels are the two sprockets that are part of the derailleur. They are part of the hanger arm that takes up the slack of the chain as you move down the gears of the cassette to lower gears.


LBS stands for Local Bike Shop
As you get more into cycling, you will probably be spending more time and money in your local bike shop.

This is a good thing as you’ll be supporting a local business, and they will also look after you with advice and often letting you try things before buying them. The odd quick fix may also be done free of charge as well if you are a good customer.

While you can often get things online at a slightly cheaper price – it’s important to support local bike shops. They will often do price matches as well if you are price sensitive.


Power meter
Used by the pro’s on tour for a number of years, power meters are getting cheaper and more accessible to us everyday riders.

Power meters measure how much power cyclists are putting through the pedals. People who use them will generally know what their FTP is, and can base the effort they put into their riding on how long they can maintain it.

Power meters are now built into pedals and crank arms – but be prepared to pay as they aren’t cheap.


The stem is the part that connects the handlebars to the forks. If you are finding it uncomfortable riding for long distances you may want to investigate changing your stem to a shorter one, or one that is more angled. Both options will put you in a more upright position on the bike.