I've been on the lookout for an expanding seatpost for my Vitus Dural 979. The previous seatpost sheared clean through & I stupidly binned it, thinking it would be easy to replace. This seatpost has an allan key bolt running from the top where the seat is secured, right down the middle of the seatpost. When tightened it draws a wedge up inside the seatpost, expanding the seatpost out against the bike frame tube. They are impossible to find. Anybody know where I could buy one?
Is that the only type of seat post you can use?
On my Vitus there is a grub screw on the frame casting that tightens into the seat post to hold it in place. As mine is a Cyclo cross frame I have also supplemented this with a clamp type fitted around the post itself which stops it dropping down.
Mercian King of Mercia Road 1980
Carlton Super Course 1980, Keith Coppell 1981
Colnago Dream 2000, Ribble Audax
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