Is it ok to use a 27.0 seatpost in a 27.2 frame. Used with a non qr clamp, would it be a solid fit? Surely it can’t make much difference….

it does! you’d need a bit of coke can at least! even then it wouldn’t be ideal.

It will just keep slipping & you’ll almost certainly be over-stressing the bolt / clamp to get it tight enough not to slip.

Even 0.1mm makes a difference! I had a bike with a seat tube that couldn’t take a 27.2mm post (should have done) but a 27.0mm post slipped so had it reamed out to 27.2mm.

Does the coke can thing really work?

It depends entirely on the quality of the engineering. My old steel kona was specified as 27.0 but a 27.2 fitted fine.

I’d be very suprised if you can fit a coke can shim in bewtween 27.2 and 27.0 (In the real world, not maths on paper that is).

You need to give it a try, but if it is anything other than a snug fit, don’t.

Anthony, old konas seemed to come as either size post – I had 2 condercones of similar ages, and one was 27.0, other was 27.2. Must have depended what tubes the factory had that week I guess.

It’ll be tricky to shim that out – shim will only need to be 0.1mm thick. If you’re desparate, try using self adhesive aluminium foil (Like this http://www.tapes-direct.co.uk/index.php?main_page=product_info&cPath=132&products_id=932 ) but make sure that you get a smooth layer without overlaps or wrinkles.

Paul, the Kona came with a 27.0 and I rode it for about 2 years before changing it to a 27.2mm!

had problem with moving seat post, (one that came with the bike so you would assume it was a perfect fit??!)which was remedied by using a little carbon grease on post. The carbon element (particles?) in the grease is enough to stop all movement………i guess what I’m trying to say is that a very small addition of somethign ‘extra’ (coke can, carbon particles for example)can make a huge difference, but I suppose that depends on the extent of the movement.

my kona is 27.2mm and i got a 26.8 and this did fit but was worried about the extra defomation on the clamp but it did fit without slipping…

My DBR had an old Tioga 27.0 chromo post when I got it. Wouldn’t stop slipping. New Thomson is a real tight fit.

I had a steel frame that happily accepted a 27 instead of a 27.2 seatpost. It never once slipped.