This is the fourth of six articles in which Paul de Vivie considers the ‘enemies’ of the cyclist.

The title line includes the expression: P(0.01+p)+0.003V2. ‘P’ is the all up weight of bicycle and rider, ‘p’ is the gradient and ‘V’ is the velocity. The first part of the formula represents something to do with rolling resistance and gravity, the second part of the formula is concerned with air resistance.

The particular ‘enemy’ that this article focusses on is rolling resistance, considering how it is affected by tyre size and pressure. Grist to the mill of any zealot who wants to engineer a acrimonious debate about the relative merits of 29ers against 650B etc. etc.... my god, I’m bored just thinking about it.

(Source gallica.bnf.fr/ Bibliothèque nationale de France)

• Publisher: T.C.F. Revue Mensuelle
• Country: France
• Date: November 1912
• Derailleur brands: de Vivie
• Derailleurs: none