Ti Donohue mini 'build' thread

[Woz]

Have seen a similar seat-post arrangement before on something from mid/late 80s. Can't remember though - Moser and Coppi bikes also set about with alternative clean looking methods in the quest for aero.

https://condorino.com/2016/09/12/legnanos-unique-seat-lug-and-binder-bolt-design/

 

[pwebb]

@Woz , yes that is pretty similar, I must say I thought it was more for aesthetics than aero and maybe also a tiny bit of weight saving - since there is no need for conventional binder bolt or ugly seatpost clamp. It does allow you to see how thin the ti seat tube is against the seat post which is both impressive and scary in equal measure. I think this arrangement would work best on thin butted steel TIG welded tubes as with ti there is a lot of welding around the hole that is needed to house it. I think it has a satisfying simplicity about the mechanism though in the same way quality U-Locks do.

 

[Woz]

Certainly clean sleek looking hiding these internal wedges. Definitely the "aero" was the fashion of the day.

Feels there is some compromise going on between weight and complexity - thinking of these too:

https://www.oldbici.it/product/shimano-dura-ace-ax-hs-7300-silver-stem-100mm-nib/

https://www.oldbici.it/product/campagnolo-nuovo-super-record-seatpost-272mm-f-moser-expander-nib/