[1] He was a son of the undefeated and multiple times Champion sire Regulus and a Partner mare.
[2] Bucephalus made his racecourse debut at Beverley in May 1768 in the Ladies' Plate of £50, where he beat Conjuror to win.
Ridden by Leonard Jewison, he won easily; beating Leith, Rambler and Baber.
At Newmarket in April 1770 Bucephalus was beaten for the first time, losing a match race to the undefeated Eclipse.
He ran several more times at Newmarket for the Earl of Farnham, but didn't win any races and was sold back to H. B. Osbaldeston in March 1773.