How To Measure A Mountain Bike Frame With Suspension

Want to buy a mountain bike to add new adventure in your life. But you don’t know which size of the bike will be ideal for you. If so, then keep reading this article. Here, we will tell you How to measure a mountain bike frame with suspension in some easy steps.

Follow the below procedure to find the correct size of the mountain bike for you.

Differences In Mountain Bike And Other Bike Sizes

You may know that the sizing method of the mountain bike varies depending on the company. The sizing system also varies depending on the type of bikes. You will be amazed to know that the hybrid and road bike usually comes with 3-4 inch height than the usual height of the cycle. On the other hand, full suspension and hardtail bike often come with the same height. Make sure to remember these measurements before you choosing a bike.

Know Different Sized Mountain Bike

As we said previously, different mountain bikes can come with different sizing method depending on the company. However, the size will be in a range. Depending on the size, there can be five variants of the mountain bike. They are XS, S, M, L, XL.

Amongst them, the XS bike comes with 12-14 inch height, and they are perfect for the rider around 5ft to 5.4ft. The S comes with 12-16inch size, and they are usually ideal for 5.4ft to 5.7ft riders. Besides, the M version comes with a size of 16-18inch and they are perfect for 5.6ft to the 5.10ft rider. The L version of the bike is around 18-20inch, and it is ideal for the riders who are around 5.10-6.1ft. If the rider is over 6.1ft, then XL version is perfect for him which comes in 20-22inch height.

Measure Your Inseam

To find a suitable bike size for you, you need to find your inseam at first. It is the length from your crotch area to your feet. You can easily measure it from your own with a measuring tape. Stand against a wall comfortably. Your leg should be slightly widespread instead of in a straight position. Now hold the measuring tape from your pubic bone to the floor. Note the measurement as it is your inseam.  

Measure The Seat Tube Of The Bike

If you already have a mountain bike, then this part is important for you. It will allow you to know whether the bike is right-sized for you or not. If you don’t know, then follow the guideline to measure the seat tube of the bike. Start with finding the top of the seat tube. It is the position where the seat clamps meet the frame of the bike. The seat tube length starts from the position to the middle of the axle, which holds the crank arms at their position. Now take a measuring tape and measure the area. The measurement you will get is the seat tube length. It should match your ideal size. Check from above to be assured whether it matches you or not.

Perform The Standover Test

The standover test is another type of test that you can do to know whether the bike is suitable for you or not. Remember the inseam measurement that you get in the previous step? Stand beside the seat of the bike straightly. Now check the size. The bike top tube length should be 2-inch higher than your inseam measurement. The top tube of a bike is the frame that went to the handlebar from the seat.

Find The Accurate Ape Index

Now you have known how tall the bike should be to suit you properly. In this step, we will know where the handlebar should drop into place for your specific torso length. In simple English, it means you will need to find out whether you can comfortably reach the handlebar of the bike from the seat. The “ape index” test will give you the measurement.

Start with measuring your arm span. The arm span is the height from one fingertip to another vertically when you spread the hands at 180 degrees. If you have a positive ape index (greater arm span than your height), then you should choose the next bigger size. On the other hand, if you have a negative ape index (greater shoulder arm span than your height), then you should go for the smaller of the two sizes.

Measure Top Ideal Tube Length

Another way is to find the ideal top tube length to find a suitable bike. You can do this by measuring the torso and arm length. Here is how you will do this:

Stand up against a straight wall and put your back against the wall. Ask someone to measure from your collarbone to your knuckles. Then find the length from your pubic bone to the hollow near your neck. Now sum the result and divide by two. Now add four with the result. The incoming consequence will be the ideal length for your top tube.

Adjust The Bike

Now you have known all the measurement of your bike. If the bike comes with a different size rather than your ideal size, you can adjust the bike accordingly for proper suitability. Start with adjusting the seat. It is straightforward to adjust. There is a nut connecting the seat clamp and the bike frame. Loosen the nut, and you can now adjust the seat. You can increase as well as decrease the seat length according to your measurement.

If you require adjusting the handlebar, then follow the below procedure:

There should be a bolt at the base of the handlebar. Find the bolt and loosen it accordingly. Use a wrench to loosen the nut. Lean forward so that your upper back make a 90-degree angle with your upper arm. The forearm should be at a 45-degree angle according to the handlebar. You can raise or low the handlebar when the nut is loosened. Tight the nut again using the wrench when you are done the adjusting.

Hopefully, the above article on How to measure a mountain bike frame with suspension will be helpful for you.

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