Seven hours and 90 kilometres into Laos and cyclists are nearing the top of the day's third steep climb. The bicycles are crawling, but the riders are smiling as they finish the last tough grind of the day.
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It started below 400 metres elevation on the Mekong River marking the Thai-Lao border, then followed a two-lane bitumen strip to a school below a mountain. Then the three-dozen riders faced a 4km 400-metre-climb in the heat of the afternoon to over 1000m above sea level.
At the top Wanchai Phutthawarin from Chiang Rai, northern Thailand, greeted riders. "Viang Phuka is only an hour. Easy riding," he said waving his left hand at the road descending the last 30km to our stop for the night, a big bottle of Beer Lao in his right.
Wanchai is one of the organisers and crew on the eight-day pedal from Thailand through northern Laos into southern China.
Good bicycles were a rarity even in the '90s, but now although still not common, it is no surprise when you do see one.
Cycling clubs and organised rides abound across the country, including Bangkok's monthly car-free day, and a growing number of Thais have made long international rides, including a select few who have pedalled around the world.
A host of bicycle tour companies offer trips of various lengths and comfort in Thailand, too. The Tourism Authority of Thailand got involved in 2002, putting resources into organising journeys through the region.
The cycling trips were called Mekong Challenges in past years and Eco Bike Tour in 2012.
As with most things Thais do, cycling trips are about "sanuk", which basically means to have fun, enjoy, but in a Thai way.
Wanchai and I have been here before. In 2008 we rode the same route. Then it was 35 cyclists from seven countries riding 600km through three countries in six days and speaking one common language every pedal of the way: bicycles.
In 2009 in a similar international group we passed this way going the opposite direction. This year included riders from a dozen of Thailand's 77 provinces, including Chiang Rai bordering Burma in the north and Narathiwat bordering Malaysia in the south. But I was the only foreigner.
Thais are welcoming people. They are delighted when a foreigner speaks reasonable Thai, but they take a perverse pleasure when you make mistakes.
Sitting in a sidewalk restaurant in Luang Namtha, Laos, after the third day riding, an easy 67km with only one steep climb, I order a Beer Lao and five glasses for the assembled riders. The waitress brings five big bottles and it's then Wanchai tells me that glass in Thai means bottle in Lao. "But, it's fine, we'll drink them."
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After an hour the group had swelled to more than a dozen and the flimsy tables were overflowing with the detritus of a minor feast of spicy salads, skewers of many meats and bowls of piping hot soup.
It's then that trip leader Pajon Jaikhla, also from Chiang Rai, says we've got to go. Where, I ask. To dinner, he says. "Dinner? What did we just do for the last hour?" "We have a banquet. With Laos officials," he says.
The banquet with more good food, more Beer Lao, monks chanting and offering their blessings, speeches and traditional dancing with nearly everyone slowly twisting their bodies to Lao music and laughing in innocent fun. Sanuk.
Laos do sanuk well. The landlocked country is one of the world's poorest but the people are friendly and easy-going. Sharing gatherings and celebrations of friendship are important and although their customs are not to be trifled with, they also match the Thais in "mai pen rai", which kind of means don't worry, be happy.
The next morning we pointed our bicycles toward China and started pedalling. For the first 7km a police motorcycle and countless local cyclists joined us.
Thailand is one of the world's top international tourist destinations, but Thais themselves still do not travel much, preferring their homeland. However, as incomes grow, more are venturing further afield.
Laos and southern China, where the food and language are similar to Thailand, are good starting points for many.
The annual cycling trips are not advertised but have become popular through a loose network of bicycling enthusiasts.
And more groups are organising tours and short trips. In a country where bicycles were once a cheap mode of transportation, they are proving a worthwhile way to travel for the growing middle class.