Bike Forums - View Single Post - Seatpost - Seat Tube Clearance

11-18-22, 06:12 PM

#28

maddog34

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Quote:

Originally Posted by Steve_sr

The Thomson post shown in the photo is 1.245" (31.62mm) The frame measures 1.265" (32.13mm). The seat tube is clearly over by .020" (0.5mm)

The post should fit without an insert. The insert is built into the frame.

This is supposed to be for a standard size 31.6mm seatpost. Is there a standard 31.8mm seatpost? Another thought... Is there a standard 31.8mm reamer? Could the wrong reamer have been used?

Guess what? the SEAT POST IS THE PROBLEM. Buy a Correct 31.8mm Post and sell that overpriced Thomson oddball as scrap. Thomson is Known for UNDERSIZED posts.... I've ran into this issue before.. they are MARKED at the correct size but are NOT the size it's marked as.
check it out....
https://bike.bikegremlin.com/3114/se...zes-standards/

tip: several Trek bikes use 31.6mm seatposts... market your ill-fitting Thomson as a Trek part.

Last edited by maddog34; 11-18-22 at 06:43 PM.

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