I don´t know how depleted the oxygen is at 16,000 feet (that´s 4850 metres to you youngsters) but it´s certainly a bit of a struggle to ingest enough.Although I´m in winter riding kit (+ heated grips) I´m still in open-face and goggles, and I´ve found that keeping my mouth open as I ride effectively supercharges the breathing. I´m fine while I´m riding, but as soon as I stop . . .

The ride from Moquegua at 5,000 ft to the Altiplano at 16,000 was a spectacular winding road through amazing landscapes. Once up there the road straightens and allows the top speed of 60mph. The rejetting has worked well, but at that height the power redustion is more than 50% according to the figures I have.

I´m now in Puno, on Lake Titicaca, down at 12,500 (3830m) and although the bike´s running rich that´s probably just as well as there´s only 84-octane fuel available in this neck of the woods.

I met a Swiss couple at the top in a Landy LWB TD5, and they were having trouble as well. They´re doing RTW in the opposite direction - shipped to NY and drove down through N America to here.