query: Who won the 1921 Isle of Man TT Senior race and by how much compared to the second and third place?
answer: The 1921 Isle of Man TT Senior race was won by Howard Davies, by a margin of 2 minutes and 3 seconds from Freddie Dixon, and Bert Le Vack, in 4 hours, 9 minutes and 22 seconds, at a speed of 54.49 mph (87.69 km/h).