Operators of minibuses on three routes notorious for speeding drivers have fitted their 110 buses with speed-limiters, weeks after the government said they would become mandatory in all minibuses. But in the three months to September, there were still 18 complaints from the public about speeding drivers. That was because the buses' speed limit was capped at 87km/h, while the speed limit on most streets was 80km/h, when the speed display device beeps a warning. Speeding by minibus drivers on the three routes - 44, 44A and 44B, which run between Sheung Shui, Tuen Mun and Lok Ma Chau - has generated many complaints. In July, a minibus on route 44A ran into the back of a truck, triggering a blaze that killed the driver and three passengers. Passengers said buses on the route always travelled at more than 100km/h. Minibus drivers on the route also have been found operating outside approved working hours. The Transport Department announced in August that all 4,350 minibuses in the city must be fitted with speed limiters by the first quarter of 2011. In less than two months, all the minibuses on the 44, 44A and 44B routes were fitted with governors, while other major minibus operators were still seeking sources for the devices. But the move has done nothing to decrease passengers' anxiety - nor their complaints. On Thursday, a South China Morning Post reporter took a ride on route 44A, which involves speed zones from 50km/h to 100km/h. The minibus' speed display unit beeped continuously for more than half of the 45-minute journey as the driver drove as close to 87km/h as he could for most of the trip. A driver called Yiu told the Post that the route's operator - Express Top Industries, one of the many companies belonging to Ma Ah-muk, the man who owns most of the city's minibuses - began installing speed limiters two months ago. 'They curb fuel supply when the speed reaches 87km/h,' he said. 'I can't go faster than that even if I wanted to.' But as their display devices are set to emit a warning beep at 83km/h - authorities have allowed a few kilometres per hour over the limit for flexibility - passengers still believed drivers were speeding even if was in a 100km/h zone. 'A woman complains every time the speed display unit beeps,' a supervisor at Tuen Mun terminus said. 'The fact that the two devices do not synchronise did give us some troubles.' The supervisor, who gave his name as Ah Kiu, said the speed limiters could not be adjusted down to 80km/h because nearly two-thirds of the journey was on the highway. All three routes pass along high-speed roads such as Fanling Highway, Yuen Long Highway and Tsing Lun Road, on which some sections have a maximum speed of 100km/h, while others are limited to 50km/h. The Transport Department had said that although it intended to cap minibuses' speed at 80km/h, a higher threshold may be allowed for routes that run on highways. A department spokeswoman said installation was voluntary, as the legislation to make speed limiters mandatory would only be discussed at the Legislative Council next year. Minibus owners have until the first quarter of 2011 to install the devices, when they will be a condition of the vehicle and passenger service licences.