Peter Kwok Ping-wah with some of his bus models.Noisy, slow and sauna-like though they were, like their British cousins, the Routemasters, they were icons that conjured up nostalgic memories of a bygone era.
"I'll miss the breeze from an open bus window - it's very invigorating," says Peter Kwok Ping-wah, a bus enthusiast and founder of the bus model shop 80M.
The city's first buses were non-air-conditioned single-deckers with a distinctive cream-coloured body and red roof. The vehicles had front-engines and open backs where travellers hopped on and off at any point that suited them - often while the bus was moving.
Vehicles with an extra storey appeared in 1949 to cope with the growing population. And the size of the double-deckers expanded from 8 metres to 12 metres long. The capacity also doubled from 80 passengers to 160.
Until the 1960s, buses had conductors aboard - one for single-deckers and three for larger double-deckers. They gave tickets to the passengers who paid the fare.
To cut operation costs, drivers became responsible for taking fares; automatic doors were also installed. Signs on the front of such buses informed passengers about the new payment method.
The downfall of "hot dogs" began in 1988 when Kowloon Motor Bus (KMB) ordered the first air-conditioned double-deckers. Road tests proved a success and soon more orders were placed.
KMB placed the last order for 30 Volvo Olympian non-air-conditioned buses in 1995.
In the early 1990s, bus companies began phasing out non-aircon models to boost service quality and become more environmentally friendly.
In 1998, New World First Bus took over China Motor Bus (CMB) and started replacing its ageing fleet with air-conditioned models. Other companies followed suit.
Yet until last Wednesday, KMB's 3,900-strong fleet included 37 non-aircon buses, serving 10 routes.
According to local bus companies, some "retired" KMB vehicles were sold to Britain as school buses. Some former CMB vehicles went to Australia to serve as open-top tourist buses. Most, though, have ended up in scrapyards.
Bus lovers like Kwok are trying to save some of these "Last Mohicans" from oblivion.
Kwok owns three "hot dogs" - including a Dennis Dragon bus with three doors. They are parked in Shek Kong. He bought them for HK$50,000 each at an auction five years ago.
They are expensive to maintain, hard to fix and break down a lot, Kwok says. Still, he loves them.
He admits that old designs are no match for the modern models. Seats have become much more comfortable - from wooden, rattan, and fibreglass to present-day bolster chairs with headrests. Also, the engines are at the back now to minimise noise. Steps near the entrances have been eliminated to favour a low-floor design. This makes it more convenient for wheelchairs users and the elderly.
"Today's air-conditioned buses, which cost HK$3 million each, are luxurious," Kwok says. "Our fleet of buses are among the world's top three."
But he is still heartbroken that the city's old buses have had to give way to newer models. That's the price of progress, he admits.