Motorcyclists are supposed to lean into corners. But when all that lies beyond each gut-wrenching turn is air - clear mountain air - the tendency is to err on the side of caution, to take each turn at a sedate speed and avoid the pickup trucks practically falling down the slope in the opposite direction, brakes screeching while passengers flop back and forth, their cheeks fleshy pancakes on the windows.
The Mae Hong Son Loop, a much ridden motorcycle route, runs through northern Thailand's lush national parks. Beginning and ending in Chiang Mai, its 600km flow around 1,864 curves, chicanes and hairpins. The views are of tumbledown forests, aeonian mountains and waterfalls hanging like blue exclamation marks amid the pines.
It doesn't take long before it begins to happen. I gently lean the bike, my body and my head into a purposeful vector aimed at the internal cusp of the corner. The only sound is the whine of the engine and the wind rushing through the helmet's vents. Tyres are sucked towards the outer edge of the corner. Trees, rocks and shrubs pass overhead. Then the 300cc Honda tilts back and devours the following ascent. At the next corner, the world is again wrenched away - this time to the right. Adrenaline surges like popped champagne and behind the visor, I'm grinning.
CHIANG MAI BOASTS many hire shops, with bikes suitable for all levels of expertise, from pootling scooters to bikes so laden with equipment, they look like they were designed to fell a Death Star.
The first challenge is to get to grips with the intricacies of the Thai road system. Having overshot the exit out of Chiang Mai twice, the journey begins with a flat burnout towards the first stop, Chiang Dao.
A rustic town with a few bars, restaurants and shops built of wood, clustered around a single main road, Chiang Dao has the feel of a sleepy Wild West frontier town. Amid the surrounding Pre-Cambrian peaks, misty valleys and forests are a couple of sweet boutique hotels, one of which is Nest. The hipster haven serves as a base from which to explore hiking routes and deep twisting caves, within which stone Buddhas recline, as if stupefied by the heat.
On the road the following day, hairpins and curves approach at a dizzying rate, steep elevations and depressions making the road seem like a dragon tearing through mountain passes and blisteringly blue skies. Despite the distractions, it's hard to get lost; the roads are clearly marked and maps are available in every small village along the way. Which means it is pointless to rely on the GPS function of a smartphone with a fast-fading battery, as I am.
The backpacker paradise of Pai emerges from the fading light just as the smartphone begins bleating dire warnings. Twenty years ago, hippies discovered the beauty of the Pai River and its surrounding valley and decided to stay. Today, it seems as though the lifestyle they envisaged is sold in standard-issue packs, dreadlocks and chillums distributed like army fatigues to saucer-eyed recruits. However, there is still plenty to recommend Pai as an overnight stop. It has great food - some of it eaten by hedonists from around the world as they saunter down the main drag - a wide range of accommodation and a festive vibe that facilitates the making of friends.
The road from Pai to Mae Hong Son is at the apex of the loop and takes about four hours to travel. In this section, dizzying climbs and ascents are punctuated by vast lengths of road, straight as needles, which tear down into wide valleys and up the other side. Such roads demand a commitment to speed. Trying to control the descent is most dangerous, although the urge to let the engine roar and enjoy the G-force pressing gently down on the gut is strong.
Although it is the largest town on the route, Mae Hong Son is quiet. Arranged around a small lake, it has the feel of somewhere that realises it has lost its popularity but is not sure why. Indeed, some riders prefer to stay in nearby Sappong, which has rougher accommodation but serves as a base for exploring the hill tribe area. Still, Baan Mai Guesthouse, in Mae Hong Son, is acceptable and, at a mere 250 baht (HK$57) for a twin room and breakfast, it will turn out to have been the best-value accommodation of the trip. Dinner is grilled squid and pad Thai bought from vendors by the lake.
On day three, crazy ascents and hairpins are exchanged for racing-style curves. This is more like it. It's such a thrill that the turning for the penultimate stop, Mae Chaem, flashes past unnoticed. An hour later, the GPS pegs my location as being 70km in the wrong direction.
It's after dark when Mae Chaem - a small town in a remote valley - finally appears. Surrounded by miles of hills and forests, this is another place that feels forgotten. When I enter, the townsfolk are in the middle of a frenzied parade to the village pagoda, as if touched by ancient hysterias and safe in the assumption no outsider will arrive to bear witness.
The final day's ride slithers up and down Doi Inthanon, which, at 2,565 metres, is Thailand's tallest mountain. The air is pine-scented and the roads are cooled by the forest's shade. Progress is slowed by the continual need to stop and marvel at the views.
Finally, it's back on the highway for another straight burnout to Chiang Mai. These last hot miles give me time to reflect. Perhaps four days was too short; there is so much to explore in the mountains, from hill tribe villages to secret monasteries hidden behind waterfalls.
Nevertheless, for its scenery, challenge and neck-bristling thrills, the Mae Hong Son Loop delivers a fantastic adventure.