How do you choose seat tube length?

How do you choose seat tube length?

The most important consideration to make as you decide which frame to go for is the effective top tube length: the distance from the head tube to the seatpost on a bike with a sloping top tube, or simply the length of the top tube on a road bike with traditional geometry.

Is seat tube length frame size?

Frame Size Bike frames are commonly measured in centimetres or inches representing the length of the seat tube. For example, a manufacturer may measure the seat tube length of a bike as 51cm, and then describe it is a small frame.

What is seat tube size?

Seat tube length is the straight line distance between the centre of the bottom bracket and the top of the seat tube.

Does seat tube height matter?

Why does it matter? Historically, Seat Tube Length was used to determine the Labeled Size of a bike. These days, seat tube length is still important in some cases: To understand the lowest position of a saddle, especially important when sizing up to a larger frame or considering a bike with a classic, level top tube.

How do you measure a seat tube diameter?

To find out the diameter of your seatpost, you must remove the seatpost from the bicycle frame and look for the size, which is stamped just below the “Minimum Insert” line toward the bottom. The number will be a three-digit number (such as 26.8 or 27.2 or 31.6).

What is the length of seatpost?

The most common size is 27.2 mm (1.07 in) for most bikes, especially for the higher-quality models. BMX bikes commonly use 25.4 seatposts. In some modern bikes with thicker alloy or carbon tubing, larger diameters such as 30.9 mm are used. Tapering seatposts often have a diameter of 22.2 mm (⅞ in) at the top.

What is the seatpost length?

Seatpost lengths range from 75mm to more than 400mm. If you’re looking for a new seatpost, make sure the length is sufficient for your needs. A too-short post can ruin the ergonomics of a bike and make riding very uncomfortable. Make sure not to overextend a short post, either.

How important is top tube length?

While effective top tube length provides a good idea of the overall length of the frame, it will be influenced by the angle of the seat tube, increasing as the angle gets slacker.

Is reach or top tube length more important?

This number is useful for identifying how long a bike will feel while in a seated position. Reach is newer way to measure a bike’s length. So Reach measures your cockpit anytime you’re standing and Effective Top Tube measures your cockpit only while seated with your saddle at a specific height.

What are the sizes of bicycle seat posts?

Seat Post Diameter. Bicycle seat post diameter on British or Italian bike frames is typically around 1 1/8 inches in diameter, or 28.6 mm. Older French frames use 28 mm seat posts, and older American style bicycle frames use a 1-inch seat post, according to Sheldon Brown , a bicycle mechanic and writer.

What is a seat tube?

The seat tube angle is the included angle between the seat tube and the top tube (assuming that the top tube is level, or the angle between the rear of the seat tube and the ground plane. Seat tube angles are most often in the range of 72 – 74 degrees on modern bicycles.

What is a bike seat tube?

The seat tube is the long tube extending from the bottom bracket upward towards the seat. And the angle of this tube relative to a horizontal line drawn at the bottom bracket represents your seat tube angle (refer to the diagram below). For a triathlon bike, the seat tube angle is typically 76-78 degrees.