Choosing the right frame size is important, getting the right fit makes riding more comfortable, efficient and at the end of the day it will make you a faster cyclist. This size guide is designed to help you choose the right frame size for you, taking into account our bikes geometry, your height, reach, and inside leg measurement to ensure the bike you choose suits you perfectly.

Mountain/Hybrid Bike Size Guide

Road Bike Size Guide

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75cm x 90cm x 45cm

How are bike sizes measured?

Bicycle measurements
British cycling

The main measurement for determining frame size is the length of the seat tube as this will define the minimum and maximum saddle height for the bike. Seat tube length is usually measured from the centre of the bottom bracket to the top of the seat tube. Mountain bikes and hybrids are usually measured in inches and road bike frames normally use centimetres. Bear in mind that the top tube length will also increase as the frame size does which will affect the reach of the bike as described later on.

Choosing the right size for you.

There are many different measurements available when choosing a bike, however, the three most important are; the riders height, inside leg measurement and reach. These need to be taken into account when looking at bike sizing and choosing the right frame size and components to suit you.


Reach is an important factor when looking at frame sizes, a bike that has a top tube that is too long for you can cause back problems and can make long distance riding very uncomfortable if you have to stretch to reach the handlebars. You need to work out whether you have a long or short reach compared to your height. To do this you can use something know as the ‘Ape index’.

Arm span and height (ape index)

To work this out you need to subtract your total arm span from your height (arm span-height). This information will be more important if you are between sizes based on your height as your reach will help you to choose whether to go for the larger or smaller of the two sizes. If you have a positive Ape index (your arm span is longer than your height) then you should choose the larger of the two frame sizes.

Stand Over Height

Stand over height is one of the most important measurements when choosing the right size for you. This is measured by the height of the top tube from the ground. The clearance between the bikes top tube and your crotch when you are stood over the bike should be approximately 2 inches.

Standover height

Standover height will vary depending on the seat tube length and the components fitted to your frame. If your inside leg measurement is shorter than the height of your top tube from the ground, then you may have difficulty controlling the bike when coming to a stop. This may also cause a problem if it means that your minimum seat height is too tall as you may find that you overstretch on your pedal stroke.

If you have any more questions about the sizing or the geometry of our bike, or you still aren’t sure what size you need, just drop us an email via our contact page and one of our expert team members will get right back to you.

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