Thomson Seatpost Clamp

You need to measure the outer diameter of your seat tube, not the diameter of the seatpost itself. Most manufacturers stamp the required clamp size directly onto the frame, or you can use a digital caliper to measure the seat tube's outer diameter at the point where the clamp sits.

While Thomson clamps are precision-machined and high-quality, always check your frame manufacturer's specific torque requirements. Carbon components are sensitive to clamping force, so using a torque wrench is essential to prevent damage to the frame or post.

It is good practice to apply a very light layer of grease to the bolt threads before installation to ensure smooth tightening. Avoid getting grease on the inside of the clamp itself, as you want that surface to maintain friction against the frame.

Thomson is known for precision machining and tight tolerances, which often results in a more secure hold with less bolt tension. This reduces the risk of your seatpost slipping during rides while providing a cleaner, more refined aesthetic for your bike.