Forum menu
So is it a good idea, say titanium frame and a carbon seatpost 27.2 to 31.-6mm? Or just get the correct size?
I never had any problems with shimming. But only do it to make what I have fit. If it's a new-build get the correct size.
But I have had to use 2 stacked shims before to get support below the toptube junction. That's a faff as the bottom shim is now stuck in there.
Doing it at the moment on an Alu frame 30.9 to 31.6 with a 100mm shim. Not sure I'd go for 4.4mm though. Sell the post and get a nice new one?
I have a road bike with a shim, first a coke can DIY one and then a proper one and it has has been fine for about 5 years. It is worth noting that I am not the lightest man to have ever graced a road bike so a fairly good test.
If the shim is long enough to spread the load properly and reaches below the TT junction it’s probably mechanically ok, but I’d treat it as a ‘get out of jail’ card rather than a preferred approach. In my view it’s probably a PITA if you regularly move your seatpost though.
I have used shims long-term with no issues on steel and aluminium frames, ali posts.