Problem Solvers 30.9 to 34.9 Seatpost Shim
Switching frames doesn’t mean you have to switch posts! Use your old posts without worry with the Problem Solvers Seatpost Shims.
This seatpost shim allows you to use a 30.9 seatpost in a 34.9mm seat tube. It has 97mm of insertion with a 3mm lip for an overall length of 100mm.