When it comes to hedonistic long-weekend retreats (as in, retreats into sin, moral laxity, and the deepest, darkest recesses of our primitive instincts), Bangkok cannot be topped. Unlike in Hong Kong, there are no restrictions on what can and cannot be worn in a bar; drinks are much cheaper; the discos are more abundant, the party scene more diverse; there are always ladies and men – and often both wrapped into one – on the prowl for temporary partners; and you're much, much more likely to see a blind singer on the street accidentally walk into an elephant.

Let's get this straight: this combination of elements has the potential to get very ugly, often with disturbing and sometimes outright criminal results (I mean, there are just some things you should never do to an elephant). But I was here to meet up with a close friend from New Zealand, a man who, like me and the rest of the chums I dragged along for the trip, is more interested in balancing atop a violently gyrating mass of steel than in anything of an untoward nature. Which is why we found ourselves spending a great deal of our Saturday night riding a mechanical bull.

It's probably not a scene the girls in the Bangkok sleaze bar were all that used to. Okay, so six drunken Western guys wouldn't have been an unusual sight to them; and our debaucherous boisterousness, I imagine, would largely have been par for the course at such a late hour. But the fact we ignored the carousel of buxom beauties at one end of the bar in favour of a mechanical bull at the other was perhaps outside the usual behaviourial paradigm. Stranger still was the fact that we appropriated a set of foam rubber spanking tubes from a staffer and used them to mete out our own punishment – on ourselves.

While one of us would gallantly ride the bull, sometimes reverse-saddling or trying to stand up on it while gripping the handle for dear life, two others would go hell-for-leather, thwacking the crap out of the rider across his kidneys, arms, sometimes head, and performing miraculous dive-smacks and tumbling-lashes in order to impress all four onlookers. It was the most exercise I've had in three years. Meanwhile, another of our party fell asleep in his seat.

It was even more fun, believe it or not, than swatting away the over-eager hands of the gaggle of ladyboys who awaited us outside the bar and launched uninvited attacks on our nether regions. Still, by Bangkok's heady standards, this was a tame evening of debauchery – merely a mid-grade hedonistic retreat, lacking the disease and Rohypnol-induced wallet losses that make it ultimate misery for less restrained souls/slugs.

But a man cannot live on copious amounts of alcohol, mechanical bovines and scantily clad dancing girls alone (even though many have died happy in the attempt), and so – after three nights of hardcore hedonism in the capital – two friends and I headed for the slightly more relaxed climes of Kanchanaburi, a small city near the border with Burma, sitting on the banks of the Kwai river.

Here we saw another side to Thailand – too often slighted because of its prolific sex trade and abundant tacky bars – enjoying non-bull-related relaxation, home-cooked meals, and the tranquility of river quiet.

Sitting in a hammock at our guest house on a balcony overlooking the water, armed with a beer and good conversation, it was the ideal place to forget the stress of the hectic life in Hong Kong. Here, far removed from mechanical bulls and self-inflicted rubber foam wounds, we could sort out the world's problems and carefully pry apart the pages of The Meaning of Life. It was almost civilised.

However, we did it safe in the knowledge that just around the corner there was an entire street of bars populated with lonely, inebriated souls just waiting for a mechanical bull to buck them back into life. After all, it was still Thailand, and there were still morally depleted Westerners looking to lose their wallets.

Hamish McKenzie