The two adventurers are heading north to Japan and then on to Alaska
Brian Milton and Keith Reynolds have notched up one world record by reaching India in just 19 days but are now diverging from the route taken by previous long-distance flights and crossing countries where this type of light aircraft has never been seen.
"We should reach Calcutta tomorrow," said Brian Milton on Monday. "From then on, it's bandit country, really.
"Every step of the way, we will be setting new records, because there's not been any microlights there before. The locals will be pretty surprised to see us."
The adventurers are heading for northern Burma, Laos and Vietnam, they will then follow the coast of China on their way to Japan and northern Russia. Then comes potentially the most difficult stage of the whole journey, as they use the Aleutian Islands as stepping stones to Alaska.
'Bureaucracy is draining'
One of the microlight's satellite navigation units has developed a fault, but Mr Milton said their aircraft would have no problem continuing, as it is only a back-up system.
He added: "Our main problems in India have been the heat, the wind and the bureaucracy. This is almost the southern-most point of our journey, and it is 110F in the shade, which is very draining, and battling with the local authorities to get clearance to fly can be even more draining.
"We try to fly at 4,000-5,000 feet, where it is a lot cooler, but it takes a long while to reach that height in a microlight.
"We have been fighting headwinds all the way across India, so it has been quite a slog, but it's only going to get tougher."
5,921 miles .. and counting
Mr Milton, 55, a financial journalist from east London, and Mr Reynolds, 45, a professional pilot from Rochester, Kent, set off on their journey on March 24.
They are celebrating the 125th anniversary of Jules Verne's classic novel, Around the World in 80 Days, and plan to retrace as much as possible the fictional route taken by Phileas Fogg.
Since taking off from Brooklands airfield, in Weybridge, Surrey, they have covered 5,921 miles.