An analysis of the 1923 World's Records, as they applied to riders of JAP engined machines, shows just how much they were dominated by Bert Le Vack. They were listed as follows:
Class A (Solo motorcycles not exceeding250cc)
500miles B.Kershaw 249cc New Imperial 50.07mph
2 hours H.LeVack 245cc New Imperial 67.84mph
12 hours Mrs G.Janson 244cc Trump-JAP 46.33mph
Class B (Solo motorcycles not exceeding350cc)
Flying start kilometre H. Le Vack 344cc New Imperial 96.50mph
50 miles H. Le Vack 344cc New Imperial 85.09mph
200 miles H. Le Vack 344cc New Imperial 77.71mph
Class C (Solo motorcycles not exceeding 500cc)
200 miles H. Le Vack 344cc New Imperial 77.71mph
Class E (Solo motorcycles not exceeding 1,000cc)
Standing start kilometre H. Le Vack 996cc Zenith 73.34mph
Standing start mile H. Le Vack 996cc Zenith 82.27mph
50miles H. Le Vack 996cc Zenith 91.71mph
100 miles H. Le Vack 996cc Zenith 89.92mph
200miles H. Le Vack 996cc Brough Superior 83.34mph
1hour H. Le Vack 996cc Zenith 89.90mph
2hours H. Le Vack 996cc Brough Superior 83.25mph
ClassB/s (Sidecars not exceeding 350cc)
Flying start kilometre H. Le Vack 344cc New Imperial 77.40mph
Class G (Sidecars not exceeding 1,000cc)
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