Mountain Bike Dimensions Explained – What Size Are You?

When I was considering making the purchase of a mountain bike online for the first time, I was hesitant to place the final order, due to the fact that I wasn’t able to try it in the store first. With so many different sizes and dimensions of these bikes, I knew there had to be a better way to find out which one would be ideal for me.

What are mountain bike dimensions and how can you find your size? Mountain bike dimensions are basically the measurements all around your mountain bike. The main measurement that is considered in this aspect is the overall height of the bicycle’s frame when it comes to adult bikes.

In order to find the correct size mountain bike for you, the process will include the two simple steps of measuring your own height and that of the frame. Once this is done, you will be able to compare your results to a chart and find out which size will best suit you.

When it comes to purchasing a mountain bike, the process is not as streamlined as it many seem from the outside looking in. Just like how you would buy a pair of shoes that is your correct size, you will need to find out which mountain bike dimensions will be the most ideal for your own measurements.

If you are looking for a solution to the questions that you have about mountain bike sizing and how to make the conclusion of which one is right for you, the information in this article will point you into the right direction. Keep reading to find out everything you need to know about bike dimensions and how you can find your own.

Mountain Bike Dimensions Explained

Mountain bike dimensions are the measurements that place each individual bike into a size category. These general size categories will correspond to riders who fit the measurement credentials in order to successfully and comfortably ride them.

When it comes to finding the correct mountain bike dimensions, it is increasingly important that the results are accurate and thorough. The size that you choose for your mountain bike will determine how you ride it, your ability to operate and steer it, as well as your potential to become injured if you are not thorough in your determination.

In this section, we will be going over an explanation of how mountain bikes are measured, from the credentials that will become the deciding factor to how these results are taken.

Rider in action at Freestyle Mountain Bike Session

Mountain Bike Dimensions Explained:

  • Length of bike frame
  • Measured from seat post to chain

The main mountain bike dimension that will be measured in order to determine the right size for each individual rider is the length of the bike frame. The frame of the bike is basically the skeleton of the entire structure.

It holds all of the individual components of the bike together, and provides a structure to the entire thing. The size of the frame will also determine how tall the bike stands, which will directly relate to the person who is riding it.

In order to find the most accurate measurements of the bike frame on your mountain bike, you will need to begin your measurement at the bottom of the seat post. With the tape measure that you are using to find this information, you will stretch it downward on the bike until your fingers meet the top of the chain.

In completing these measurements from the seat post to the chain, you will be able to cover the entire area of the actual bike frame itself, leaving out any unnecessary components while including everything that is important.

Throughout the rest of this article, we will be diving into the topic of the measurements that you need to find your correct mountain bike dimensions, with an explanation of how you can find your real size using a detailed chart.

Keep reading to find out everything you need to know about mountain bike sizing, what to measure, how to find the right bike for you, and everything in between.

How To Find Your Correct Mountain Bike Dimensions

Now that you have gotten a basic understanding of the concept of mountain bike dimensions, you might be wondering how you can find out which size is right for you. After all, this is why you searched for mountain bike dimensions in the first place.

If you are looking to find the perfect sized mountain bike for you, then you have come to the right place. In this section, we will briefly be going over the credentials that you will need in order to find out what your correct mountain bike sizing is.

Take a look at the list below for a short outline on the process of finding your true bicycle size.

How To Find Your Correct Mountain Bike Dimensions:

  1. Determine your height in feet and inches (including your inseam length)
  2. Measure the size of the bike’s frame
  3. Compare the two measurements on the chart to determine your correct size

First and foremost, you will need to know what your exact height is, measured in feet and inches. This is very important to know for sure, instead of guessing, due to the fact that accurate measurements will give you the best results.

The ideal mountain bike dimensions for every rider will depend solely on their height, and the rest of the process is just balancing it with the vehicle. Since you will be sitting up on your mountain bike when you are actually riding it, the length of where your legs are reaching will determine how well you can ride.

The measurements of your total height will also include the separate measurement of your inseam, or in other words, the inside of your leg. Both of these measurements will be used to compare to the size of the actual bike.

With the seating arrangements on a mountain bike having such a great affect on the form that the rider is able to carry out, it is increasingly important that this particular credential is properly measured before proceeding.

The next piece of information that you will need in order to begin locating your correct mountain bike size is the length and height of the bike’s frame. This is important because the size of the actual bike itself will need to match your size so that the ride will be comfortable.

The rest of this process basically consists of taking the two measurements that you put together, with one being your height and the other a measurement of the frame’s height, and comparing the two in order to find the correct ratio.

The right mountain biking size is basically just a balance somewhere in between the two measurements. If you are too tall for the length of your mountain bike frame, you will not be able to properly operate it. On the other hand, if your bike is too tall for you, then you will run into the exact same problem.

This is why it is vital that you take these measurements correctly to avoid any mistakes that you could potentially notice when it is too late.

In the next section, you will be able to find an easy to read chart that will help you to locate your correct size once you have found your measurements.

What Size Mountain Bike Do I Need?

At this point, we have established some information about mountain bike dimensions as well as the basic information that you will need in order to find the right one for you. So, how can these results be compared to find the most ideal mountain bike?

Well, after you have taken the measurements of your own height as well as that of your mountain bike frame, the difficult part of this process will have already been completed. The only thing left to do is match your results with those in this section.

Take a look at the table down below, where you will find the correct answer for which size mountain bike you should choose for yourself.

Mountain Bike Sizing:

  • 4’10” – 5’2”: 12 inch frame
  • 5’2“ – 5’6”: 17 inch frame
  • 5’6” – 5’10”: 21 inch frame
  • 5’10” – 6’1”: 26 inch frame
  • 6’1” – 6’4”: 30 inch frame
  • 6’4” – 6’6”: 35 inch frame

The items that were listed in the above outline cover the most average ranges of height, from just over 4 feet to over 6 feet tall.

In correspondence with the height of the rider, there is a specified inches count for how high the correctly proportioned mountain bike will measure.

The average frame sizes will fall anywhere between 12 inches and 35 inches, depending on the total height of the rider and the length of their inseams. The sizes can also be classified throughout the ranges of X-Small to XX-Large, as outlined in the next list in this section.

Mountain Bike Measurements And Size Classifications:

  • 12 inches = X-Small
  • 17 inches = Small
  • 21 inches = Medium
  • 26 inches = Large
  • 30 inches = X-Large
  • 35 inches = XX-Large

After you have completed all of the necessary measurements and compared your results to the previous chart in order to find your correct mountain biking dimensions, you will be able to more easily find the exact product that you are looking for with a search that broadly classifies the size group of the bike that you are seeking out.

Mountain Bike Dimensions For Children

Mountain biking is a fun and enjoyable activity for everyone involved, no matter how old or tall the rider is. Children can also be avid participators in the sport, and will consequently need to find out which mountain bike dimensions are ideal for their height as well.

In this section, we will be briefly discussing the height and bicycle measurements for kids, in the same fashion as the adult sizes were discussed previously.

Kids’ Mountain Bike Dimensions:

  • 3’ – 3’5”: 12 inch wheel
  • 3’5 – 3’9”: 14-16 inch wheel
  • 3’9” – 4’5”: 18-20 inch wheel
  • 4’5” – 5’: 24 inch wheel
  • 5’ and more – 26-27 inch wheel

Contrary to the chart that was listed in the previous section, children’s bike sizes will not be measured by the frame size, but instead the total height of the wheel. So, when you are in search of a perfectly fitting mountain bike for your little adventurer, you will need to consider these factors instead.

Once the child surpasses a height of 5 feet, you will be able to move on to the adult sizing chart and purchase the corresponding sized mountain bike.

How To Find The Correct Saddle Height

When it comes to finding the right mountain bike dimensions for your height and the length of your legs, the decision process does not stop at this comparison. In fact, there are even more factors that will influence how well you will be able to ride your mountain bike.

One of these factors is the height of your saddle, or the seating area of the mountain bike. When you are choosing the correct frame height of the bike, making sure that your seat is properly adjusted is just as important.

In this section, we will be going over the process of how you can make sure that your saddle is in the correct position for the best possible experience on your mountain bike.

Take a look at the list below for a few simple steps the you can follow in order to come to the right number.

How To Find The Correct Saddle Height And Adjust Accordingly:

  • Sit on your mountain bike near a wall
  • Lean your back up against a wall using your elbow
  • Push your leg down, remaining parallel to the ground (as low as possible)
  • Adjust the saddle height up and down until your knee is bent slightly (in the back)
  • Test out the height on a ride
  • Play with the forward and backward adjustments

To begin the process of finding your correct saddle height, you will sit on your mountain bike just like normal, directly in front of a wall with your back to it. Lean your back up against the wall using the tip of your elbow on the wall itself.

At this point, both of your feet should be firmly planted on the ground as you are leaning, keeping the bike in one position for the purposes of this expierement.
You will then begin to push your leg down, while making sure that your leg stays parallel to the level of the ground. In doing this, you will need to push your leg down as far as it can possibly go without breaking this position.

Next, you will begin to adjust the saddle height up and down as you are still sitting on it until your knee becomes slightly bent. This bend will come from the back of the knee, and the adjustment process should come to an end when you see any amount of movement in this area.

Once you have found the setting that you feel is correct for your height, you can take it outside for a quick test ride. During this ride, you should be paying attention to how you feel on the bike, and if if needs a little bit more adjusting to be perfect.

If you have found that the height adjustment is correct but something else is just uncomfortable about it, you can try to play with the forward and backward adjustments of the seat.

Keep doing this until the saddle is perfectly positioned to where you are comfortable throughout all of your rides without the need of any additional adjustments.

As you can see, there are plenty of factors that go into finding the correct size mountain bike for you. With all of the sizing possibilities that exist in the world of mountain biking, it is important that you stay ahead of the game and get prepared with your ideal mountain bike size.

When making a purchase of a mountain bike, especially when it is more expensive, the last thing that you will want to do is waste money on something that will not work for what you need it for. Instead, you should educate yourself on how you can find these measurements, as well as why they are important to calculate in the first place.

Now that you have found out almost everything you need to know about mountain biking dimensions from point A to point Z, you will have more than enough instructions to be able to make an informed decision on your next mountain biking purchase.

Whether you have been intending to buy a mountain bike online or you would just like to make sure that you are purchasing the right one in the store, you will certainly benefit from the helpful advice that was offered throughout the duration of this article.

Mike Rausa

I'm a 42 year old married father of 3 that fell in love with mountain biking late in life. Mountain biking quickly became my go to fitness activity. I created this blog to help beginners to advanced riders with tips and strategies to improve your riding experience. More About Me...

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