The rainy season does not change from year to year in SEAsia. It is from may/june to september/october with august and september as the months with most rain. But of course one year is not exactly like another year and it can be huge variations from year to year. In 2011 it was huge floodings and blocked roads, roads washed away etc and affections all the time up until january/february the next year until all roads were cleared and passable again.

There have been experienced overlanders/RTW riders on this forum who have been forced or chosen to stop their ride in SEAsia during the rainy season because of.....rain. Just to have that mentioned.
Its not only thats its a bit more unpleasant to ride in rain, its much more dangerous too. The traffic in SEAsia isnt as in EU, US etc. They have no idea about for example aquaplaning on rainy roads and there are heaps of pick ups and other vehicles overturned and smashed in the ditches just after a little shower there.

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Hi Snakeboy.
you are right, the rainy season is in summer. But the floods you are mentioning took place in Winter...so not exactly in the rainy season. (Nov. 2011) If you look at the rainy days, they occur mostly in the summertime. But when and hpow much it will be raining is constantly changing. Same as Winter in europe, December/January isn´t the coldest month in winter anymore in most areas. Snow isn´t seen until late February where I live (and my neighboors rely on the snow for their ski business...)
Flowering of plants started in early Dec. this year in my garden....well i think climate is changing and it is unpredictable and it might change from year to year.
i´m travelling Asia for almost 30 years now and I experience a change in climate which is unpredictable.
And thanks on your advice about the traffic and weather, maybe there are some readers who didn´t know.

So again my advice:

it´s absolutely possible to ride the LOS in rainy season without problems. during the rain, you just take a break, and as soon as it stops you go on. Or move to a dry area (as I did numerous times in India, Ceylon and the LOS)
On a small bike with low weight it shouldn´t be any problem. The locals don´t stop life (or riding their 100cc bikes)...
Just be aware, that the monsoon is weak in some years and strong when El Nino hits.
I myself can´t change my shedule too much and will have to ride temporarilly in the rainy seasons. It´s a question of beeing able to adapt to the situation. If you are in a hurry, your tour through Tibet is planned and the Visa is about to expire, well that´s a problem then, and if even trucks cannot pass, you won´t either. But that´s the risk of travelling.
I wouldn´t hesitate to ride in the rainy season, just because it could get wet and I could get stuck. (and I encountered real monsoon in times where it was predictable and when we stood knee high in water, within some minutes...)
But that´s just my opinion.

Oh dear - the rainy season is in the..... rainy season. Not in the winter, not in the summer, not in atuumn or spring. Theres no point linking european seasons up to asians as there are no equvivalence.

There might be a bit of a climate change going on but it doesnt mean that one can look away from seasons totally or even a littlebit. In fact it makes weather who often is unpredictable even more unpredictable. To advise people to tale off during the hardest rainy season in Asia just because a flower happens to bloom in mid europe in february is with the respect totally nonscense. Would you send someone off to Prudhoe Bay in Alaska or Nordkappin northern Norway for the same reason?

In 2011 in Thailand during the floodings there it rained in august and in september opposite of what you insinuate and it continued into october and a bit into november too.

Its however one thing thats unclear from the threadstarters side and that is that he only says atuumn and he doesnt mention which months he is thinking about. Does he mean august and september or maybe october and november?
If he means august and september I would advise not to go to Thailand, Laos Cambodia and Vietnam. On the other hand I would advise him to go to Indonesia and Borneo. They still have dry season there at that time and wonderful islands and roads to explore. Strange that a guy who says he has been travelling to Asia for 30 years did mention that?
If TS want to go in october/november I would say just go to Thailand, Laos, Cambodia etc but be aware there still gonna be some rain there.

To advise someone to go to a place and ride motorbikes in the hardest rainy season is quite a remarkable advise if you ask me....

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In the end everything will be fine. If its not fine its not the end....

Snakeboy is right. You can still get a lot of rain in Cambodia in October. November will be mostly dry but a shower now and then is still possible.

A Cambodian registered bike can go to Laos and back without any problem. According to the last info entering Vietnam also shouldn't be a problem anymore (on a Cambodian registered bike).

Renting is definitely cheaper in Cambodia than in Laos.

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