Death

On 6 April 2003, during the first race of the MotoGP season at the Japanese Grand Prix held at the Suzuka Circuit, Kato crashed hard and sustained severe head, neck and chest injuries. He hit the wall near the Casio Triangle chicane of the circuit at around 125 mph (200 km/h).

The Accident Investigation Committee determined that Kato crashed when he lost control of his motorcycle, which entered a near high-side state, followed by an uncontrollable oscillating weave resulting in his leaving the track and striking the barrier.^[2] Initially he and the bike struck a tire barrier, followed by a foam barrier. There was a gap between the tire and foam barriers, and Kato was severely injured when his head struck the edge of the foam barrier, dislocating the joint between the base of the skull and the cervical spine.^[2]

Questions were raised regarding the actions of the corner workers immediately following the crash. Kato was thrown back onto the track after hitting the barriers and was lying next to the racing line.^[2] Depending on the type of race (endurance or standard), when a motorcycle or rider is incapacitated on the race track, a red flag is waved and the race stopped, or in endurance races and British Superbike Championship events, the safety car is called on the circuit to neutralise the race so the motorcycles are packed-up behind the said vehicle at slow speeds, so the track can be safely cleared. This did not happen following Kato's accident. Instead, the corner workers moved him onto a stretcher and off the circuit. The race was not stopped. Kato's crash was the first fatal accident to occur during a Grand Prix motorcycle racing race session at Suzuka Circuit; his was the last motorsport fatal crash at the circuit until Jules Bianchi at the 2014 Formula One Japanese Grand Prix.

The Investigation Committee noted: "According to images broadcast during the race, four rescue workers took hold of Kato, who lay collapsed face up in the middle of the course, held him by the right shoulder, the torso and both legs, and moved him sideways just a few dozen centimeters onto the stretcher. It certainly appears that sufficient care was taken to immobilize his head and neck area. However, when the stretcher was moved Kato's head drooped markedly, and it cannot be denied that this might have additionally injured his neck."^[2]

Kato spent two weeks in a coma following the accident before dying as a result of the injuries he sustained. The cause of death was listed as brain stem infarction. Many of the MotoGP riders wore black armbands or placed small #74's on their leathers and bikes at the following race in South Africa to pay tribute to the fallen racer. His teammate, Sete Gibernau, thereafter wore a #74 on his racesuit since winning the race in his memory. There has not been a Grand Prix motorcycle race held at Suzuka following Kato's crash, with safety issues at the facility being cited as the reason.

During the 2003 Suzuka 8 Hours race held that July, Honda paid tribute to Kato, a two-time Suzuka winner, by bearing his racing number on the Sakurai Honda bike of Tadayuki Okada and Chojun Kameya (who in Turn 1 crashed on spilt oil on the second lap), along with the bikes of Nicky Hayden and Atsushi Watanabe. Once Okada and the others returned to the pits with their broken bikes, Okada was permitted to go back out with a spare bike, as a mark of respect, but was ineligible to win since his original bike was badly damaged. Two hours later, he returned to the pitlane to retire the bike amid mass applause from the crowd. At the end of the race, the other Sakurai bikes of Yukio Nukumi and Manabu Kamada (who were still racing), went on to the rostrum to show off Kato's helmet bearing his number on the visor, and a photo of him on the bike, as a mark of respect.

Afterwards the FIM retired Kato's number, and the bike number 74 has not been used by any rider since. The FIM named him a Grand Prix "Legend". Satoshi Motoyama, a fellow Japanese racer driving in the Super GT and a childhood friend of Kato had the latter's racing number on his helmet ever since Kato's death.^[3]

Tributes

A month after the crash, on 18 May Honda organised a day whereupon 9,000 people including his last team owner, Fausto Gresini, attended their Aoyama building in Tokyo, where a shrine with exhibits to Daiji-chan had been created.^[4] Former British American Racing Formula One driver Takuma Sato led a tribute by expressing his condolences of the death to his friend Daijiro Kato during 2003 San Marino Grand Prix weekend as a test driver.^[5]

In 2006, the Misano World Circuit honoured Kato, who lived part of the season in the area, by naming a new access road to the circuit Via Daijiro Kato. That circuit's offices are located on the road named in his memory.

Kato's #74 racing number

Grand Prix motorcycle racing