Choosing the perfect mountain bike frame size can be tricky, especially if you’re buying your first bike online. However, getting the right size is crucial since it can ensure a comfortable, efficient, and safe ride.

In this guide, we’ll show you how to measure mountain bike frame size so you can find the perfect fit for your Ultra Light Carbon Hardtail MTB SDY20 bike.

Step 1: Determine Your Height

To start measuring your mountain bike frame size, you need to determine your height first. Stand against a wall without shoes on and measure from the floor to the top of your head. This measurement is your height.

Step 2: Calculate Your Inseam Length

Your inseam length is the distance from your crotch to the floor. Stand against a wall, place a book between your legs, and measure the distance from the top of the book to the floor. This measurement is your inseam length.

Step 3: Use a Frame Size Chart

Once you have your height and inseam length measurements, use a mountain bike frame size chart to determine the right frame size for you. Generally, you should look for a frame size that’s between 1 to 4 inches shorter than your inseam length. For example, if your inseam length is 29 inches, a frame size of 15” to 18” should be a good fit.

Step 4: Test Ride Different Sizes

While the frame size chart can give you a good estimate, the best way to find the perfect fit for your UL Carbon Hardtail MTB SDY20 bike is to test ride different sizes. Most bike shops allow demo rides, so take advantage of these opportunities. When testing different sizes, make sure you adjust the saddle height, handlebar position, and pedals to mimic your riding position.

Step 5: Consider Your Riding Style

Finally, when measuring your mountain bike frame size, consider your riding style. For example, if you’re a downhill rider, you may want a bike with a longer top tube and shorter stem. If you’re a cross-country rider, you may want a bike with a shorter wheelbase and longer stem. Make sure you choose a frame size that’s suitable for your riding style.



Getting the right mountain bike frame size is essential for a comfortable and safe ride. By following the steps we've outlined in this guide, you should be able to find the perfect fit for your Ultra Light Carbon Hardtail MTB SDY20 bike. Remember, the best way to determine the right size is to test ride different sizes and consider your riding style. Happy riding!