Gaston Rivierre, French, 1862 - 1942
Here we see a 61 year old Gaston Rivierre mending a puncture during the 1923 edition of the Critérium des Vieilles Gloires (which might translate as the Criterium of the Dodgy Old Has-beens). Gaston was an early enthusiast for 'vet' racing - and may even have been a prime mover in its invention. If so, he has a lot to answer for.
And I like the spectator wearing the tie, trousers with knife edge creases and an Ecky-Thump hat.
Aside from being an accomplished cyclist, Gaston patented a number of derailleur designs of his own, including a very early design for a parallelogram derailleur
(Source gallica.bnf.fr/ Bibliothèque nationale de France)