The 1923 Isle of Man Tourist Trophy saw the introduction of the first Sidecar TT race over 3 laps, won by Freddie Dixon and passenger Walter Denney using a special Douglas motorcycle with a banking-sidecar in a time of 2 hours, 7 minutes and 48 seconds, at an average speed of 53.15 mph (85.54 km/h).
The fastest Sidecar lap was by Harry Langman on a Scott at 54.69 mph (88.02 km/h).
The Senior race was held in poor weather and local course knowledge allowed local Isle of Man competitor Tom Sheard, also riding a Douglas, to win a second TT to add to his first win in the 1922 Junior TT.
TT novice Jimmie Guthrie suffered a machine breakdown in the Junior 350 cc race, but he achieved six victories in later years.
[1] Changes to the course occurred in 1923 with the adoption of a private road between Parliament Square and May Hill in Ramsey.