What diameter seatpost do I need?
27.2mm
The dimensions of the seat tube can vary from bicycle to bicycle, so when choosing a seatpost, it’s important to get the correct diameter. The most common diameter is probably 27.2mm, but other sizes between 21.15 and 35mm are often found, as well. Seatposts also vary in length.
Are all seat posts the same size?
While there are any number of post diameters out there, most modern road and MTB bike frames accept a seatpost of either 27.2mm in diameter (‘standard’), 30.9 or 31.6mm (‘oversize’).
What size seat clamp do I need for a 28.6 seatpost?
Note: The seat clamp diameter needs to match the diameter of your seat tube rather than your seatpost, which is a little smaller. For example, a 27.2mm seatpost (a size commonly found on road bikes) fits inside a 28.6mm diameter seat tube, so it’s a 28.6mm clamp you need.
How do you measure saddle height?
The saddle height is always measured with the crank arm pointed down and in line with the seat tube. The distance from the center of the pedal axle to the top of your saddle is your seat height….Heel method
- To start with, raise your saddle roughly to your hip.
- Sit down on the saddle and touch the pedal with your heel.
How is seatpost offset measured?
It’s measured from the seatpost centerline to the center of the clamp….Most manufacturers do this:
- trace an imaginary line (or tie a string) along the center of the seatpost entry into the bike a few inches down the seat tube.
- extend that straight line past height of the seat rail clamps on the post.
What are the sizes of seat posts?
Seatpost diameters generally range from 22 mm to 35 mm in 0.2 mm increments. 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.
What size seat clamp do I need for a 25.4 seatpost?
28.6
25.4 seatpost = 28.6 seatpost clamp.
How do you measure a seat tube diameter?
To measure, you place the rod inside the seat tube and match the diameter. The rods are designed to have an increasing diameter from one end to the other. Therefore, the correct reading, which matches, is the one above the end of the seat tube.
How do I know if my bike seat is too high?
Strain in the back of your knee, or irregular sharp pain in its side, it’s likely your saddle is too high – so adjust the height as you would for wobbly hips. But another area you may want to check is your cleat or shoe position on the pedal. Your cadence shouldn’t be characterised by pointed toes.
How do you adjust seatpost height?
Place your heel on the pedal and pedal backwards to reach the six o’clock position. Your knee should be completely straight. If your knee is still bent you need to increase the height, adjusting in small increments each time, and if your heel loses contact with the pedal then you need to lower the saddle.