Any advice gratefully received!

I have an on-one scandal, Ringle 27.2mm seat post and Hope 31.8mm seat clamp. Can’t seem to get the post to stay where its set. I can tighten it enough so it won’t rotate and seems solid but even on my commute it is slowly moving downwards!

Could it be the seat clamp doesn’t extend far enough down the seat tube or is it a problem with the frame? Or is there variation between manufacturers – if so, who makes a ‘big’ 27.2mm seat post

Thanks in advance

Thoroughly clean your seatpost and the inside of your seattube with some degreaser. Then apply a thin layer of non-teflon grease and see if that helps!
Oli

Ragley make a 27.3 for worn/oversize frames, crc had em in, or try some pace carbon shield anti seize stuff, it’s got little bits in to reduce the clamp force required
I’d try a different clamp first though

I had the same problem on holiday a few weeks ago. Problem sorted when I cleaned post and inside tube.

Cleaning it is then, if not, new clamp

Ta

Problem with On Ones I’m afraid, don’t know why.

Fixed my 456 with a bolt-up clamp, for my Scandal I use a Salsa Flip Lock which seems to do the trick.

APF

Mine is a bolt up clamp already!

Bosh!

There is this..

You’re welcome! 😀

Nice one bikewhisperer!

It’ll be the last thing to use but you have allayed my ‘bought a dodgy second hand frame and its useless’ fears!

Chromag or Salsa clamp. Sorted.

No worries!

I have the same problem with a steel frame.. Was a poorly made prototype and every seatpost I’ve tried either creaks or slips. That double clamp would be great for me if it was 28.6/27.2…

I’ve clamped the seatpost at the insert point with a 28.6 seatclamp and some front mech shims.. It buts up against the real seatpost clamp and stops it dropping. Seems to work for the moment, but also going to try a 400mm post for more inset and less torque on the clamp

EDIT: they do a nicer looking one too:
here

Clean it properly with degreaser and then use carbon fibre grip paste. Sorted.

if it is a QR seatclamp then try lubing the QR mechanism with something like GT85 – will allow you to get better tension before you think it is tight.

My post on my Bridy folder was slipping – I degreased the tube and the post – roughed up the inside of the tube with wire wool/files, etc. It was lubing the seatpost clamp that finally sorted it.