In the following season he established himself as a good performer in handicaps, winning five races including the King George V Stakes at Royal Ascot and finishing second in the Jockey Club Cup.
Klairon was a representative of the Byerley Turk sire line,[3] unlike more than 95% of modern thoroughbreds, who descend directly from the Darley Arabian.
[4] Shangamuzo was one of several winners produced by his dam French Fern, a high-class racemare who won the Ribblesdale Stakes in 1960 and was rated 118 by Timeform.
[6] After finishing unplaced in his first two starts over seven furlongs, Shangamuzo ran in a twenty-two runner maiden race over a mile at Sandown Park Racecourse in October.
Later that month he was sent to Royal Ascot and recorded his first major success in the King George V Stakes and was then stepped up in distance to win a minor event over two miles at Newcastle Racecourse.
On his next appearance, Shangamuzo defeated Alverton by one and a half lengths in the Top Rank Club Handicap at Newcastle to win his fifth race of the season.
At Royal Ascot, he ran in the two and three quarter mile Queen Alexandra Stakes and finished second behind the six-year-old John Cherry, who, as a gelding, was not allowed to compete in many of the major staying races.
In his second attempt to win the Jockey Club Cup, Shangamuzo led from the start but was caught inside the final furlong and was beaten three quarters of a length by Grey Baron.
At York, Shangamuzo was beaten two lengths by Smuggler when attempting to concede three pounds to his rival, but was widely expected to reverse the form at level weights over a longer distance at Sandown.
Smuggler did not contest the Gold Cup, his owner, Lord Porchester stating that the unfashionable status of stayers as breeding stallions meant that it would devalue the horse to even enter him in the race.
In the Goodwood Cup, Shangamuzo conceded weight to his rivals and led for most of the way but was caught in the closing stages and finished third behind Tug of War and the three-year-old Arapahos.
[11] In 1975, the independent Timeform organisation did not give a rating to Shangamuzo but awarded him a "p", indicating that the colt was likely to make more than normal progress, and commented that he was certain to stay one and a half miles.
[11] In their book A Century of Champions, based on a modified version of the Timeform system, John Randall and Tony Morris rated Shangamuzo as an "inferior" winner of the Gold Cup.