ADVICE please - seatpost

[FireMountain95]

Hi, looking for some advice on this one please..

I have a Raleigh Torus Ti XT, frame soon to be built up. A previous owner has ridden an undersized seatpost leading to a crimped seat tube. The tube is still circular, calipers measure a consistent 27.6mm inner diameter. Hard to tell what is was originally, I’m guessing maybe a 30.0mm?

Kalloy seatpost for the build comes in 27.4 or 28.0mm.

What to do?

1) Thin shim and use the 27.4mm post?
2) Will it be possible to gently prize apart the post opening allowing 28.0mm to fit?
3) take it to someone with the right tools, try and get it back to original size?

Any advice welcomed.... Thanks.

 

[rabbid]

Hi, lovely frame! How about measuring the outside diameter just above the seat stays. Then you can substract wall thickness and you should get the original diameter for your seatpost. I personally would try not to use a undersized seat post. I do have a Zaskar which was fitted with a 26.8 seat post instead of 27.0 and the matching seatpost fits MUCH better than the undersized one. Nevertheless, it will be quit some work to get the diameter back to the original size.

Cheers

 

[mk one]

Yes, my last Torus was 30.0.

Personally i would get the tube sorted, ideally i would want the seatpost in contact with the tube all the way down, not just at the top where its tightest.