What size road bike do I need?

26-07-21 | Simon

Getting the right size of road bike is almost more crucial than with any other type of bicycle. As you spend a lot of time in essentially the same riding position it is important to be as comfortable and as efficient as possible. If you aren’t comfortable then you simply won’t enjoy riding. Finding out the right size can be a bit daunting but it can actually be quite a simple process. And remember, it’s the frame size that has to be right, you can always change handlebar width and stem lengths to suit your body shape a little better further down the line. Road bike frame sizes are traditionally measured in centimetres with the typical sizes running from 48cm through to 60cm in two centimetre increments. Some brands are starting to simplify this a little by changing to easier to understand measurements such as labelling frames from XS (extra small) to XL (extra large). Simply put you need to match the frame size to your height (and to some extent your leg length:torso length ratio).  

If you are looking at a reasonably modern bike from a recognised brand (Specialized, Trek etc) then your first stop to determine frame size is the brand’s website. Most brands will publish a sizing guide that can be used to pretty accurately determine the right size for you. Bare in mind some brands do this better than others and also a lot of us sit between two sizes. If this is the case then your next stop should be your friendly local bike shop. These are the professionals and can almost instantly help you with the correct sizing. One thing to consider here is that your nearest bike shop might not stock the brand you are looking at so you might need to travel a bit further afield to find the right shop. 

You also need to consider the age of the bike you are looking at. Trends in bike sizing and component choice have changed a lot over the past few years. Ten years ago most road bikes followed the trend for ‘aggressive’ race geometry where the rider ended up being quite stretched with a lower front end; great for an experienced rider/racer but not that comfortable for a new rider. More modern bikes have seen a push towards making them more comfortable even for experienced riders and racers. Front ends have been raised which brings the handlebars up and reduces the impact on a rider's shoulders and neck. There has also been a more obvious split into different types of road bike so it should be easier to identify a bike that is more comfortable than another.