In Ireland, we are blessed with endless trails best explored on mountain bikes. From lough side forest trails to rugged mountain routes, we have it all. Whatever your level of experience, your mountain bike adventures will be more fun on a bike that fits properly.
A correctly sized mountain bike will absorb the off-road bumps and prevent jarring injuries caused by the wrong size bike. Like people, mountain bikes come in many different shapes and sizes. To work out which size is best, follow our guide below.
What Size Mountain Bike Do You Need?
1. Start With Your Own Measurements
When shopping for a new mountain bike, you will need to have some of your own measurements to hand. Before heading out to buy a bike, measure:
- Your height
- Your inside leg
You probably already know your height. If not, then check your height by:
- Standing against a wall looking straight ahead (you should have no shoes on).
- Mark the wall at the top of your head.
- Step away and measure from the mark on the wall to the floor.
To measure your inside leg enlist some help first to make it easier:
- Again, stand against a wall with no shoes on.
- Ask your helper to measure from the floor to level with your crotch.
Write down both measurements in centimetres and inches and bring them to The Edge with you.
2. Understand How Mountain Bike Frames Are Sized
Typically mountain bike sizes start at extra-small and go up to extra large. There are also manufacturers who make XXS and XXL mountain bikes. Mountain bikes are built differently from hybrids and racers, so it’s essential to make sure you use the right kind of size chart for reference.
The bike size measurement that is shown on a size chart (like the one below) typically refers to the length of the seat tube. This is the tube that your bike seat slots into. To measure the seat tube length, measure from the top down to the centre of the bike chainring. If you are comparing an old bike to a size chart, be aware that some manufactures use different measurement methods.
There can be some variation between frame sizes from different manufacturers, with one’s medium frame being slightly different from another’s. Some mountain bike manufacturers also have their own sizing guides. We advise trying a few different makes of the same sized bike to find the one that fits best. When trying out bikes instore, remember that seats and handlebars can be adjusted for a better fit.
3. Understanding Mountain Bize Weights
Mountain bike weight isn’t something that is included in the bike size charts, but it is something to consider. Modern mountain bike frames are mostly made from lightweight aluminium and alloys. Thanks to these super strong lightweight materials, a bigger bike frame doesn’t mean a much heavier bike.
What really changes the weight of the bike frame, though, is the mountain bike type. A hard tail mountain bike for example has less hardware than a full suspension mountain bike. Depending on the rider’s strength and size, this can make the ride very different. When you are trying out bikes for size, keep the bike type and how you will use the bike in mind.
4. What To Do When Your Between Bike Sizes
It is often the case that a rider’s measurements suggest that one of two bike frame sizes are suitable. In this scenario, we can’t recommend enough that you buy a mountain bike that you have tried first.
The bigger bike size is usually advised when a rider is between to sizes. This allows for better control and a more comfortable ride. With a smaller frame, there may be a need for modifications that may or may not affect how the bike performs.
What feels right is the tried and tested measure when choosing between two bike sizes. Trust your body to tell you if it feels too cramped or too stretched.
5. Mountain Bike Size Chart
| Bike size | Frame size | Rider height |
|---|---|---|
| Extra-small | 13 -14in | 152cm – 162cm (5ft – 5ft 4in) |
| Small | 14 – 16in | 162cm – 170cm (5ft 4in – 5ft 7in) |
| Medium | 16 – 18in | 170cm – 178cm (5ft 7in – 5ft 10in) |
| Large | 18 – 20in | 178cm – 185cm (5ft 10in – 6ft 1in) |
| Extra-large | 20 – 22in | 185cm plus (6ft 1in plus) |
6. Understand Mountain Bike Wheel Sizes
You won’t get far on your new mountain bikes without wheels. What wheels you choose depends on how you will use your mountain bike rather than the size of the frame. Your size is also a factor to consider. Taller and larger riders usually prefer a bigger sized wheel, whilst smaller riders find smaller wheels more comfortable to control.
There is growing popularity amongst seasoned riders for 29 inch wheels, commonly known as 29ers. Anyone new to trail and mountain biking should keep in mind that 29ers are fast rolling wheels. This can make them harder to control. Incidentally, bikes with 29 inch wheels have problems fitting on some bike racks.
The most manageable wheel size to control, whilst not compromising too much on speed, is the 27’5 inch wheel. This is the most popular size amongst mountain bike riders who only use their bikes off road and on mountains. The smaller 26 inch wheel is an all-round good fit but has less agility than the slightly larger wheel.
Talk to an experienced rider at The Edge to find out what wheel will go best with the frame you have chosen and the riding you enjoy.
7. Mountain Bike Fitting Service
Still unsure about choosing the right size mountain bike? We offer an instore bike fitting service to help you choose the perfect mountain bike. Get in touch to arrange a bike fitting.
The team at The Edge are also happy to offer advice by phone or email, call us on +353 (0)21 432 0522 or email [email protected].
Why Choose The Edge For Your Mountain Bike Needs?
At The Edge, our team at our Cork store is made up of competitive cyclists and triathletes. All on hand to offer you their experienced advice.
We won’t be beaten on price or service and offer free delivery on orders over €50 to anywhere in the Republic of Ireland. The Edge is Ireland’s leading Bike, Running, Swim and Triathlon Shop in Ireland. We offer a great choice of thousands of products with new stock arriving regularly. To contact our sales team and for advice, call us on +353
