trek 17.5 taille

Choosing the correct frame size is a crucial component of getting the most out of your road bike. It's not just about comfort: when a road bike fits properly, it's more efficient, easier to handle, and better at transferring your power to the road.

Bikes come in a range of sizes. The best fit for you depends primarily on your height and inseam. That's true whatever your gender, as gender matters far less in finding the bike that's best for you than other factors. Every rider deserves a bike that fits and feels great, no matter their body type, style of riding, or level of experience. That's why we make great bikes for everybody and every body. If you find that you're in between sizes, choose the smaller size for a more aggressive position if you are more flexible or prefer lower handlebars. Choose the larger size for a more relaxed position with higher handlebars. Or, reach out to your retailer or our experts here at Trek HQ for a quick consult.

The Trek Size Finder

This online tool helps determine the bike size that’s best for you. You’ll need a measuring device for your height and inseam. If you find you’re between sizes, we recommend contacting your retailer or calling us at 800-585-8735 (M–F) for a quick consult.

Road bike size chart

Expert advice from Trek

Online resources are great, but there’s nothing like a real person. You can connect with your local Trek retailer directly, call and chat online with us at Trek Headquarters, Monday - Friday 8 am - 6 pm CT and Saturday - Sunday 9 am - 6 pm CT, or email us. We’re here for you.

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Bike Sizing Guide: What Size Trek Bike Do I Need?

Written by  Gary Johnson / Fact checked by  Henry Speciale

Are you looking for a bike to buy and asking yourself “what size Trek bike do I need?”

Trek bike sizing is very straightforward and varies by type.

For example, mountain bikes follow a unique method called alpha sizing that uses designations such as small, medium, or large. Using this system, a 5’3” to 5’7” tall person can use a 17.5” frame size.

On the other hand, Trek road bike sizing takes into account the inseam length.

If you want to get on the road or hit that trail with your ideal two-wheeler, check out our sizing guides below.

Table of Contents

1. Trek Mountain Bike

2. trek road bike, 3. city & hybrid bike size chart, things you can consider before choosing a trek bike size, helpful tip, trek bicycle sizing guide.

Trek bikes are comfortable and easy to ride, making them excellent for beginners. They also come in different dimensions, so you should find one that fits you perfectly.

Whether in inches or cm, our Trek bike size chart will help you match your height with the appropriate vehicle.

Unlike other brands, Trek bikes have upgraded their MTB sizing with alpha classifications to remove guesswork for customers.

You may find that your chosen model has some and not all of the sizes in this Trek MTB size chart. In that case, branch out and look for XS and XXL options if the Trek M/L frame size doesn’t fit you.

Note that the women’s bike size chart also uses the alpha sizing guide for their line of women’s mountain bikes though the height requirement is slightly different for each size.

Did You Know

The Trek Marlin 5, which is a popular trail mountain bike, uses the alpha sizing chart, but its size is not limited to XS – XXL only! Trek also offers an XXS with 26” wheels for this MTB type.

Trek has given us 4 categories when it comes to road bicycles. These include:

• Aero – The best aerodynamics for speed and performance
• Endurance – Provides comfort perfect for long hours of riding
• Time Trial – Speed-focused bikes with unique designs
• Climbing – Lightweight bikes excellent for uphill climbing

Designed to be a mixture of road and mountain bikes, Trek hybrid bicycles are best used for casual rides and commutes.

What size bike should I get? What does “size” really mean? And what is the best way to find the correct model for yourself?

There are usually FOUR different aspects that you must consider and have a good idea about.

Riding Style

Do you want to ride your bike for fun or use it for racing and exhibition? Regardless of your budget, it is important that you consider the type of biking you want to do. Some people prefer to ride in the city, while others prefer to cycle off-road.

Trek bikes come in various sizes depending on the vehicle’s discipline, since some frames have different geometry to provide the support their riders need.

Rider Height

Most bicycle models come in different sizes for different body types so that they fit most people well.

The height of a person, when measured from head to toe, can help determine the bike size that would match them. This is because taller people have longer upper and lower extremities compared to shorter people, which means they will need different sizes of bikes in order to ride comfortably.

Inseam Length

After careful deliberation with the above two factors, the frame size is then ultimately determined by your inseams or the distance from your crotch to the bottom of your leg.

You should take this into consideration because it will determine how much room there is between your feet and handlebars when sitting on the saddle comfortably.

Practical Use /Test Ride

Last but not least, once you have chosen your bicycle size and Trek model, test out the bike with at least a short ride. This will let you assess the balance and comfort of the chosen vehicle.

Whether you ride recreationally or professionally, you cannot choose blindly. First, bikes are expensive, and second, you must buy the correct product to use it for a long time.

If you’re done with our Trek frame size chart, Trek’s online website also has a unique feature that helps you select the correct frame size. You can try their bike finder, which asks for your riding style, height, and even inseams before arriving at a recommendation.

In case you haven’t noticed, there is a lot of variation in bicycle sizing, and looking for the size I need for my height was not a walk in the park.

Well, I hope our guide answered your question about what size Trek bike do I need. Should you have any more questions, send us a message.

Read more: Choosing the Ideal Bike Size for Your Kids – Bicycle Sizing Guide.

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