Specialized Rockhopper Comp 2025 Bicycle - Green
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Do you want to receive your bike ready for use? Don't forget to add the bike assembly service at the time of purchase! Discover all the details here: Francesconi bike assembly
A Complete Guide to Bike Sizes
Foreword: Not all bike sizes are the same
Each type of bike has a specific frame and often uses a different size scale. For example, a road bike with a 54cm frame might be considered a medium size by one brand, but a large by another.
Bicycle adjustment margins
Some types of bikes, like gravel bikes, offer a wide range of adjustments, adapting to different body types. Other models, however, have limitations in this regard. This is an important aspect to consider.
How to use size charts
We've created a simple guide to help you find the right bike size:
- Check out our size charts for each bike type.
- Learn more with specific tips to help you make the right choice.
Size Charts: Find Your Perfect Bike
Gravel and road bikes
Sizes are based on the length of the top tube (in cm), which determines the reach of the bike.
| Cut | Recommended height | Horizontal tube length |
|---|---|---|
| XS | Up to 157 cm | 48-50 cm |
| S | 157-167 cm | 50-53 cm |
| M | 168-178 cm | 53-56 cm |
| THE | 178-185 cm | 56-58 cm |
| XL | Over 185cm | 58-62 cm |
For gravel, measurements may vary slightly due to different geometries, but remain similar.
Mountain bike
MTBs are measured in inches, based on the seat tube.
| Cut | Recommended height | Size (in inches) |
|---|---|---|
| XS | Up to 157 cm | 14"-16" |
| S | 157-167 cm | 15"-17" |
| M | 168-178 cm | 16"-19" |
| THE | 178-185 cm | 18"-20" |
| XL | Over 185cm | 20"-23" |
Sizes also vary depending on the type of MTB: full-suspension , hardtail or fat bike .
Children's bikes
The size depends on the size of the wheels, often associated with age:
| Age | Wheel Size |
|---|---|
| 1-3 years | 12" |
| 2-4 years | 14" |
| 4-6 years | 16" |
| 5-8 years | 20" |
| 8-10 years | 24" |
| Over 10 years | 26"/27.5" |
What to do with half measures?
If you are between two sizes:
- Comfort : Choose the larger size.
- Performance : Go for the smaller size.
Final tips for choosing
- Consult the manufacturer's instructions : Always check the brand's guidelines.
- Ask an expert : a specialized workshop can help you choose based on your height, ideal reach and goals.
- Test the bike : If possible, test the model you intend to purchase.
