I want to put a rack on my Cotic X – it is theframe without the rack mounts. Does have unused canti brake bosses but I think a seatpost clamp adapter will work best for me. Thinking about a Tubus Disco rack (light, strong, cheapish)

I need something like this:
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but for a 27.2mm seatpost, Cotic says the clamp must be 29.8 or 30mm. Really struggling to find one in this size – they are either 31.8 or 34.9mm. Anyone here know where to find one?

I believe Edinburghbicycle do another brand with another size

Would this be any good from Charlie?

It’s a salsa clamp that you can fit anywhere on your post.

It mounts straight onto the post so you would still need your original seat clamp.

but for a 27.2mm seatpost, Cotic says the clamp must be 29.8 or 30mm

You’re confusing seatPOST size with seat CLAMP size. They are not the same thing my friend, and bike with the same size post can have different sized clamps too. It’s the external diameter of the top of the set tube which matters.
🙂

Thanks Peter but I am aware of the difference – the seat post is 27.2 – so I need a 30mm clamp – as per my post.

Amplebrew – thanks, that would work I guess. Seems pricey for what it is and a clunky solution – I like the Mpart one – just need the right size!

Thanks Jamie – the ETC one at Edinburgh comes in 28.6, 31.9 and 34.9mm options…..

Think I am going to get the OMM White Rock instead – mounts to brake bosses.

clanton – Member
Amplebrew – thanks, that would work I guess. Seems pricey for what it is and a clunky solution – I like the Mpart one – just need the right size!

That’s cool.

I’d imagine the Salsa clamp would be a well sorted bit of kit, although admittedly I’ve no personal experience.

M-Part make what you are after, available from Wiggle. You want the smaller size. Had one on my paddy wagon for ages, works flawlessly.

EDIT: the Koma also has a 27.2 seatpost and is probably made of the same steel tubing. You definitely want the small.

Have you looked at one of these beam rack
I’ve used it with both the slide-on top bag and panniers. I use the different sized rubber packers for each bike.

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I had one of those snap at the clamp point,it was more of a 😯 for the rider behind me 😉 .It wasn’t overloaded (honest guv),I just think after a bit of mileage (2000ish) it had stressed the alloy with all the micro springboarding that must go on. I bought another one as they are a great solution (and quick fix ) for no braze ons. This time around I now have some extra supports P-clipped between the seat stays and the tapped holes in the rack.