Seat Clamp Size

Guys,

My new frame has a 30.4mm outer diameter seat post tube. I need to get a larger clamp. I am looking at the Hope ones on CRC. Trouble is what size?

Do I go for 31.8 and hope that it'll compress down enough to clamp the post or go for one of the other manufacturers who do a 30.0 and hope that I can squeeze it on thus ensuring it will clamp down?

Cheers

Even more confused but there's light.... Underneath the seat clamp that (only just) doesn't fit is printed 34T. I just found the tech spec on the frame and it says 34.9.

So 34.9 it is then (just bigger than the 34T hopefully). I thought the measurement related to the diameter of the seat tube it's meant to clamp. Maybe its the max diameter it'll fit around.

Your seat post size should be written on your old seat post, or measure it across or inside the frame, which will give you the size. The seat post diameter is smaller than the diameter of the frame where your seat post sits but 31.4 is the size of a Scott Genius post. It sounds to me like you have a 27.2 or 28.something. I have a 31.4 post if you would like to buy it.

Cheers, I know the seatpost size is 27.2 but when I measured the seat tube size outer diameter (frame) in order to buy a clamp it measured 30.4 and didn't relate to any seat clamp sizes being advertised. I have since learnt that its 34.9. The new 34.9 clamp fits fine.

I think we got confused between seat post and seat tube.


Cheers.