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100% Irish Owned

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When buying a new bike, one of the hardest things to figure out is what bike size you need. With this in mind, we have created this bike size guide to help you narrow down your search. 

Finding the perfect bike size for you is essential to ensure comfortable, efficient and fun rides. A few factors will determine the size you should get. 
First, the type of bicycle you choose plays an essential role in the bike size you need. MTB, road bikes and hybrid bikes are all designed with different frame shapes, which affects the sizing. Your height is the second major factor in determining your bike size. Finally, your riding style, use, and personal preference will play a role in your bicycle size choice. 


Two measurements are needed to help you find your bike size: your overall height and your inner leg length. 
Measure your length with your shoes on, as this will help you get a more accurate fit. 
Your inner leg length is the length between the floor and the top of your inner leg. 
If you are between sizes after taking these measurements, your reach will be the deciding factor. You can determine your reach by measuring your ape index, which is your arm span minus your height. If your ape index is positive, then go for the larger frame. If your ape index is negative, then go for the shorter one. 


As previously stated, the type of bike you are buying will also determine the size you need. A mountain bike will defer widely from a road bike sizing, and electric bikes do not size the same way hybrid bikes do. 
You might also want to go for a smaller bike if you prefer to ride aggressively or a longer one if you are more of a leisurely cyclist. 


Typically, there are three types of sizes for bikes. Road bikes will use sizing in centimetres and descriptive dimensions, like small, medium, and large. Mountain bikes will use measurements in inches and descriptive sizes. Hybrid bikes will use the three sizes options, while e-bikes will, on the whole, use the X-Small to XXX-Large system. 
These measurements differ depending on the brand and range. We'd recommend you check the product page size guide to get an accurate size guide. 
Bike dimensions are calculated by measuring the seat tube length from the centre of the ball bearing or the centre of the bolt attaching the crank arms. 


The stand-over height of a bike refers to how tall the frame is from the ground. It is measured from the top of the top tube to the floor. Ideally, you want 2cm of clearance between you and the frame. For example, a bike with a stand-over height of 75cm would suit someone with an inside leg of 77cm. 

Having gone through the essential measurements to determine the ideal bike size, you can refer to our size guides at the top of the page to help you choose the size you need. 
However, please note that our guides serve as general advice, and you should always refer to the individual size guide on each product page for accurate measurement. If you need further information, please do not hesitate to contact us

And, if you want to get a deeper analysis of your ideal bike size, we recommend you have a look at our bike fitting guide where we explain in detail the subtleties of a personal bike fit.