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Adult bike size guide

What bike size to choose based on your body type?

The bike size is a fundamental criterion to ensure a comfortable position and better performance. An unsuitable frame can cause back, knee, or wrist pain.

Whether you're looking for a city bike, mountain bike (MTB), or road bike, it's important to consider your height, leg length, and riding style. A frame that is too large will force you to stretch unnecessarily, while a frame that is too small will restrict your movements.

Tip: For a perfect fit, choose a frame that matches your inseam and consider adjusting the saddle and handlebar height.

Find your ideal bike today! Discover our latest bicycle arrivals: road bikes, MTBs, and e-MTBs.


Guide Summary

  1. Road bike size guide
  2. MTB size guide
  3. Road bike tire size guide
  4. MTB tire size guide
  5. Glove size guide
  6. Cycling clothing size guide
  7. Knee pad size guide
  8. Elbow pad size guide


Size guide for choosing your road bike

To calculate your road bike frame size, it is necessary to know your height and the size of your crotch. Once the measurements are taken, perform the following calculation and refer to the table below:
Crotch x 0,65 ≈ road frame size
Crotch x 0,885 = saddle height for the road (from the middle of the bottom bracket to the top of the saddle).

Your sizeYour crotch sizeSize of your road bikeSize of your road bike
152 à 160 cm 68-73 cm 48-50 cm S
161 à 162 cm 73-74 cm
163 à 164 cm 74-75 cm 50-52 cm
165 à 166 cm 75-76 cm M
167 à 168 cm 77-78 cm
169 à 170 cm 78-79 cm
171 à 174 cm 80-81 cm 53-54 cm
175 à 178 cm 81-82 cm L
179 à 180 cm 83-84 cm
181 à 182 cm 85-86 cm 55-56 cm
183 à 186 cm 87-88 cm
187 à 188 cm 89-90 cm 57-60 cm XL
189 à 192 cm 91-92 cm
192 à 200 cm 93-94 cm ≥ 61 cm XXL

What road bike size to optimize your performance?

A well-fitted road bike will allow you to adopt a comfortable aerodynamic position and prevent muscle strain.

How to determine the right size?

  • Measure your inseam length and refer to our size chart.
  • Consider your riding style: a more aggressive position for racing, a more upright position for comfort.
  • Ensure that your frame allows proper adjustment of the saddle and handlebars.

Enhance your road cycling experience with the right bike size!

How to choose my road bike?


Size guide to choose your MTB

To calculate your MTB frame size, it is necessary to know your height and your crotch size. Once the measurements are taken, perform the following calculation and refer to the table below :
Crotch x 0,56 ≈ MTB frame size
Crotch x 0,88 = MTB saddle height (from the middle of the bottom bracket to the top of the saddle).

Your sizeYour crotch sizeSize of your MTB / inchStandard size
152 to 160 cm 73 cm 38 cm / 14 inches S
161 to 162 cm 74 cm
163 to 164 cm 75 cm 41 cm / 16 inches
165 to 166 cm 76 cm 41 cm / 16 inches M
167 to 168 cm 77-78 cm
169 to 170 cm 79-80 cm 44 cm / 18 inches
171 to 174 cm 81 cm
175 to 178 cm 82-83 cm 46 cm / 18.5 pouces L
179 to 180 cm 84-85 cm 50 cm / 20 inches
181 to 182 cm 86-87 cm
183 to 186 cm 88-89 cm 52 cm / 21 inches
187 to 188 cm 90 cm
189 to 192 cm 91-92 cm 55 cm / 22 inches XL
192 to 200 cm 93-94 cm

How to choose the right MTB size for optimal comfort?

For a comfortable and efficient ride, selecting the right MTB size is crucial. A poorly fitted mountain bike can affect your stability, performance, and even your safety on technical trails.

  • Frame size: It directly depends on your height and inseam length.
  • Type of riding: A downhill MTB requires a more compact frame than a trail MTB.
  • Riding position: Finding the right balance between maneuverability and comfort is essential to prevent muscle pain.

Hesitating between two sizes? Choose the smaller one for better handling or the larger one for more stability.

Discover our range of MTBs adapted to your body type!

Guide to choosing the right MTB


Road bike tire size conversion chart

Typically, the road bike tire size is displayed in the following format (exemple : 700x25c) 700 is the size of the wheel (in this case this example corresponds to a standard wheel used by 99% of cyclists) and 25 is the tire width in mm.

For aesthetic and aerodynamic concerns, it is preferable to opt for a tire of the same width as the rim. In this regard, remember that once inflated, the tire can be one or two millimeters more than the size indicated by its expansion.

Recommended tires for road bikes : 700x23c for climbers (light and more aggressive relaunches), 700x25c for punchers and sprinters (the most common size), 700x28c for more comfort (generally used by endurance riders).

Recommended tires for gravel road bikes : from 35 to 42mm wide.

What are the correspondences in Inches / ETRTO / FR measurements / circumference?

InchesETRTOFrench sizesCircumference
26” (kids) 20-571 650x20c 1990 mm
23-571 650x23c 2075 mm
40-571 650x40c 2120 mm
54-571 650x50c 2100 mm
28” (adults) 20-622 700x20c 2100 mm
23-622 700x23c 2125 mm
25-622 700x25c 2135 mm
28-622 700x28c 2150 mm
30-622 700x30c 2160 mm
32-622 700x32c 2170 mm
35-622 700x35c 2185 mm
37-622 700x37c 2200 mm
40-622 700x40c 2220 mm
42-622 700x42c 2230 mm
47-622 700x47c 2250 mm
50-622 700x50c 2280 mm
54-622 700x54c 2295 mm
60-622 700x60c 2330 mm

Find the perfect tire for your bike!

Whether you're a climber, sprinter, or gravel enthusiast, choosing the right tire enhances your performance and comfort. Opt for a width suited to your riding style for better grip and durability.

Discover our selection of bike tires!

Tips for choosing your road bike tires


How to choose your MTB tires?

Usually you will see MTB tire sizes as (exemple : 27.5 x 2.20") 27.5 is the size of the wheel and 2.20 is the width of the tire expressed in inches.

MTB tire standards

  • The wheel size of an adult MTB : 26”, 27.5”, 27.5” Plus and 29”
  • The different assemblies : Tubetype*, Tubeless Ready* and Tubeless*
  • The maximum width allowable by the frame and fork of the MTB
  • Folding and wired tires

MTB tire / rim width compatibility table

To choose the front tire, refer to the admissible fork dimension while for the rear tire you will need to know the admissible width in relation to the frame. Check this information on the manufacturer's documentation.

The width of the rim should also be taken into account.
Here is a table giving the compatibilities knowing that the most frequent widths are between 1.4 and 2.6 inches:

Tire width in mmTire width in inchRim width in mm (hook rim)
18 0.7” 13C
20 0.8” 13C
23 0.9” 13C 15C
25 1.0” 13C 15C 17C
28 1.1” 15C 17C 19C
32 1.2” 15C 17C 19C
35 1.4” 17C 19C 21C
37 1.5” 17C 19C 21C 23C 25C
40 1.6” 17C 19C 21C 23C 25C
42 1.7” 17C 19C 21C 23C 25C 27C
44 1.7” 17C 19C 21C 23C 25C 27C
47 1.8” 17C 19C 21C 23C 25C 27C
50 1.9” 17C 19C 21C 23C 25C 27C
52 2.0” 17C 19C 21C 23C 25C 27C 29C
54 2.1” 19C 21C 23C 25C 27C 29C
57 2.2” 19C 21C 23C 25C 27C 29C
60 2.3” 19C 21C 23C 25C 27C 29C
63 2.4” 19C 21C 23C 25C 27C 29C
66 2.6” 21C 23C 25C 27C 29C

Equip your MTB with tires suited to your terrain!

Whether you're riding on technical trails, in the forest, or on rocky terrain, choosing the right tires directly impacts your grip, comfort, and performance. Find the width and tread pattern that match your riding style.

Discover our range of MTB tires!

Tips for choosing your MTB tires


Cycling gloves size grid

Your road bike gloves size and MTB gloves size are determined by two measurements:
A - The width of your palm excluding the thumb
B - The length of your middle finger

Take the average of your two measurements, either : (A+B)/2. Then refer to the table. If you find a size in between, choose the one above.

Europe Size 1 2 3 4 5 6 7 8 9 10 11 12
Average obtained (A+B)/2 1 cm 2 cm 3 cm 4 cm 5 cm 6 cm 7 cm 8 cm 9 cm 10 cm 11 cm 12 cm
International Size Y3XS Y2XS YXS YS YM YL XS S M L XL XXL

Ride with perfectly fitted gloves!

Good grip, optimal comfort, and effective protection: choosing the right glove size is essential for better control and increased safety. Don't let the cold, vibrations, or moisture ruin your rides!

Find the perfect pair of gloves!

What are the best bike gloves?


Vest sizes / Back protector / Cycling bib shorts

Item size S M L XL
Chest size (cm) 84 - 89 90 - 95 96 - 101 102 - 107
Waist size (cm) 74 - 79 80 - 85 86 - 91 92 - 97
Hip circumference (cm) 84 - 89 90 - 95 96 - 101 102 - 107

Ride in Comfort and Safety!

Whether it's to improve your protection, optimize your comfort, or enhance your performance, well-fitting gear makes all the difference. Find the ideal size for your vests, back protectors, and cycling shorts and fully enjoy every ride.

Discover our selection of cycling apparel.

How to dress for cycling?


MTB knee pads sizes

Item size XS S M L XL
Thigh circumference (cm) 32 - 35 36 - 39 40 - 43 44 - 47 48 - 51
Calf circumference (cm) 25 - 28 29 - 32 33 - 36 37 - 40 41 - 44

Protect your knees without compromising comfort!

Well-fitted knee pads provide optimal protection while ensuring ideal freedom of movement. Whether it's for MTB, BMX, or enduro, choose the right size to ride safely.

Find your perfect knee pads!


MTB Elbow pad sizes

Item size XS S M L XL
Biceps circumference (cm) 18 - 21 22 - 24 25 - 27 28 - 30 31 - 34
Forearm circumference (cm) 17 - 20 21 - 23 24 - 26 27 - 29 30 - 33

Ride safely with the right elbow pads!

Good elbow protection is essential to absorb impacts and prevent injuries in case of a fall. Be sure to choose the right size for a perfect fit and optimal comfort on all terrains.

Discover our selection of bike elbow pads!

How to protect yourself while riding MTB?


Why choose the right bike size?

A bike that fits your size ensures more comfort, safety, and performance. It reduces muscle fatigue and enhances your riding pleasure, whether in the city, on the road, or off-road.

Need help choosing? Check out our complete guide and find your ideal bike in just a few clicks.

Browse our selection and find the perfect bike for you! See our bikes


FAQ – Choosing the right bike size

 

Which bike size for which height?

The choice of bike size depends on your body shape, particularly your height and inseam. Here are some guidelines:

  • Under 1.50m: XS bike or 24 inches
  • 1.50m to 1.60m: S bike or 26 inches
  • 1.60m to 1.70m: M bike or 52-54 cm for a road bike
  • 1.70m to 1.80m: M or L bike, frame between 54 and 56 cm
  • Over 1.80m: L or XL bike, with a frame of 56 cm and above

 

Tip: If you're torn between two sizes, go for the smaller one for more maneuverability or the larger one for more comfort on long rides.


What size bike based on age?

For kids, the bike size is mainly based on their height and age:

  • 2 to 4 years (85-100 cm) → 12-inch bike
  • 4 to 6 years (100-120 cm) → 14 or 16-inch bike
  • 6 to 8 years (120-135 cm) → 20-inch bike
  • 8 to 10 years (135-150 cm) → 24-inch bike
  • 10 years and up (more than 1.50m) → 26-inch bike or XS/S adult size

 

Advice: Choose a model with an adjustable seat to accommodate your child's growth.


What's the difference between a 24 and 26-inch bike?

24-inch bikes are typically for children and young teens who are between 1.30m and 1.50m tall. They are lighter and easy to handle to suit younger riders' physiques.

26-inch bikes, on the other hand, often mark the transition to adult bikes. They are suitable for riders over 1.50m and are popular for MTB and city bikes, offering more stability and better performance on roads and trails.

Note: Nowadays, 27.5 and 29-inch bikes are also common for MTBs, offering improved performance on rough terrain.


What size bike for a person who Is 170 cm tall?

If you're 1.70m tall, here are the recommended sizes based on the type of bike:

  • Road bike → Frame of 53-55 cm
  • MTB → Size M
  • City bike or hybrid bike → Frame of 52-54 cm

Note: The bike position can vary depending on your riding style. A slightly larger frame is often more comfortable for touring, while a more compact frame offers better maneuverability for sporty riding.


Need help choosing?

Check out our complete size guide and find the perfect bike for your body shape!

Explore our selection of bikes suited to your size!

 

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