New Zealand and Australian racing Crosby moved from his home in
Renwick, New Zealand to
Auckland in the late 1960s and began a motorcycle apprenticeship at a local
Kawasaki dealership. By 1979, he was racing in the Australian
Superbike championship for the Australian importer for
Pops Yoshimura's motorcycle racing parts company. The following year, Crosby qualified a Moriwaki Kawasaki on
pole position at the 1979 Suzuka 8 Hours, ahead of all the major factory racing teams. Moriwaki provided Crosby with Kawasaki motorcycles to compete in the
Formula TT world championship and the Isle of Man TT.
Suzuki factory sponsorship Crosby's impressive results earned him
factory backed sponsorship in 1980 with the
Suzuki Grand Prix racing team, operated by their British importer, Suzuki GB. Crosby was forced to start on the back row of the starting grid due to a minor rules infringement during qualifying but, charged through the entire field of competitors enroute to an upset victory over
Freddie Spencer, whose Honda was underpowered compared to Crosby's Yoshimura Suzuki. He then won the
Ulster Grand Prix to secure the Formula One Class of the 1980 Formula TT world championship. Crosby's string of victories with four stroke machinery earned him a reputation as a four stroke specialist. Although Crosby was contracted to ride for Suzuki, he decided to sponsor Gardner to compete in the 1981 British Superbike championship riding Kawasakis run by the British Moriwaki concession owned by Crosby. In the
Daytona 200 race, Crosby was forced to retire due to a transmission problem. Crosby made a strong impression by winning the pole position at the season opening
Austrian Grand Prix held at the fast
Salzburgring. Crosby ended the 1981 season with a victory at the prestigious
Mallory Park Race of the Year.
1981 TT Formula One championship Crosby's defense of his TT Formula One title was successful as his Suzuki GS1000 outclassed the Honda RC1000 of his leading rival,
Ron Haslam.
1982 Agostini Yamaha Crosby believed that he would be contracted with Suzuki to race their latest RG500 motorcycle in the
1982 500cc world championship however, it became apparent that Suzuki would only provide him with year old motorcycles. He had tentatively agreed with Honda to compete in the
AMA Superbike Championship when,
Giacomo Agostini offered him a contract to race for the
Yamaha factory racing team with
Graziano Rossi as his teammate. He followed this with a victory at the Imola 200 race in April. While Yamaha had introduced a new 500cc
V4 engine for
Kenny Roberts, coded YZR500 0W61, the Agostini-Yamaha team was left to race on the older Yamaha
square-four cylinder YZR500 0W60 motorcycle. Crosby jumped into the lead at the start of the season opening
Argentine Grand Prix however, he was forced to retire after a couple of laps due to a
crankshaft failure. He qualified on pole position for the
Austrian Grand Prix but fell to fourth place in the race when he encountered handling issues with his motorcycle. Crosby followed with another fourth place finish in the
Spanish Grand Prix. A poor start at the beginning of the
Nations Grand Prix left Crosby in mid-field however, a spirited ride saw him improve to third place, passing Kenny Roberts before the end of the race. The rain drenched
Dutch TT was stopped after only six laps when Crosby and several other riders crashed on the wet track surface. After the race was restarted, Crosby made an impressive result by finishing the second leg ahead of Roberts to secure fourth place overall. His Yamaha suffered another crankshaft failure putting him out of the
Belgian Grand Prix however, he recovered to finish the
Yugoslavian Grand Prix in second place behind eventual world champion
Franco Uncini. Crosby crashed during practice for the
British Grand Prix badly scraping the skin on the palms of his hands however, after sitting out Saturday practice sessions, he valiantly fought to a third place finish in the race. While Yamaha had put all their efforts into developing their new V4 engine, they had stopped development work on Crosby's square-four Yamaha allowing it to lose ground on the opposing teams from Suzuki and Honda. When Roberts was forced to withdraw from the championship due to injuries sustained at the British Grand Prix, his V4 Yamaha was given to Crosby for the
San Marino Grand Prix however, after he suffered a high speed crash during practice he decided to race on his familiar square-four Yamaha, finishing in third place behind Freddie Spencer and Randy Mamola. Crosby attempted to ride the V4 Yamaha during practice for the season ending
German Grand Prix but, he declared that the experience had taken years off his life. He reverted to his square-four Yamaha for the race but, crashed while trying too hard to keep up the pace on the under powered motorcycle. Despite competing with an older and slower motorcycle, Crosby was able to use his riding skill and determination to finish second overall in the championship behind
Franco Uncini. Frustrated by the internal politics of his race team, Crosby quit the Grand Prix circuit after the 1982 season. ==Later career==