Lot No: 324
1924 Triumph 3½hp Model R 'Ricardo' Racer
Frame no. 339975
Engine no. 91950 HRI
Triumph's early output was confined to side-valve machines, but in 1921 the appearance of the Coventry firm's first overhead-valve model caused a sensation. Based on the existing SD ('spring drive') model, whose frame and engine bottom end it inherited, the newcomer sported a four-valve cylinder head designed by automotive engineering consultant, Harry Ricardo. Although the 'Riccy' was unsuccessful at the Isle of Man TT races, a works bike ridden by Frank Halford broke the world flying mile record in 1921 with a speed of 83.91mph.
The first production models arrived in 1922 equipped with a cast-iron rather than the racer's steel cylinder barrel, but otherwise were much the same, featuring paired parallel valves set at 90 degrees in a pent-roof combustion chamber, bifurcated inlet port and separate exhausts. Druid girder forks were fitted until Triumph's own design was ready. Economy rather than