MCW Metrobus
KMB resumed the evaluation of air-conditioned double-decker in the late 1980s, unlike those evaluated in the early 1980s, all these buses evaluated had the air-conditioning directly driven by the main engine. In 1987, the trial of one air-conditioned MCW Metrobus was started, but it was unsuccessful and the bus had its air-conditioning removed. Later Leyland Bus delivered one air-conditioned Olympian to KMB and the bus entered service in 1988, it was successful and later KMB started to place orders of air-conditioned Olympians (the prototype Olympian was finally withdrawn in 2005 and was preserved). An air-conditioned Dennis Dragon, which was also successful, was evaluated by KMB in 1990.