After 10,000 miles (16,000 kilometres), eight countries and one rescued passport, a group of 30 intrepid motorcyclists are now a quarter of a way through their epic 40,000 mile round-the-world adventure.

The international riders, led by official BMW Motorrad travel partner Globebusters (which organised the trip for Edelweiss travel) have just left the Chilean city of Santiago and are now headed to Los Angeles in the same country. Since setting off on November 21, they have been battered by freezing temperatures in Europe, travelled desert roads in Africa, been whipped by extreme winds in Patagonia, endured torrential rain in Argentina and, finally, felt the sun on their backs in the 30 degree climes of South America.

"We're on schedule, although we did have some problems in Patagonia which almost put us behind," says Kevin Sanders, who is leading the expedition. "There were general strikes in Chile (over rising gas prices) which affected borders and ferries – I had to adjust the route slightly to avoid the protests and that meant we got more time on the gravel roads of Ruta 40 in Argentina. The wind on that road tries its best to push you off and into the deep piles of gravel – this year they were the strongest I've ever experienced. It caught a few riders off guard, and they ended up picking the stones out of their motorcycle bash plates."

The group of riders, some of whom have paid up to $100,000 for the full eight months, have all settled in well according to Kevin. "It always takes a bit of time to get ‘bike fit'," he says. "The most common thing is that people bring too much and we soon see them sending unused items home. People's riding experience varies and although most have done one or two smaller tours before, this is the biggest ride any of them have ever done. Some found the gravel roads in Patagonia a challenge. Most riders have a similar story – they're here because they've worked hard all their lives and now's their time to enjoy things. It's taken them a while to realise they don't need to rush around any more, they should slow down and smell the roses."

Kevin says each day's riding is planned to appeal across the group: "Some days are tougher than others. We have a good mix of roads to keep everyone happy and have our fair share of difficult conditions. The extreme rain in Argentina caused a few riders to crash as the roads were really slippery," he says. So far, highlights have included the "superb twisties" and coast roads of the Atlas Mountains, with dramatic views of the Atlantic Ocean and medieval coastal cities. Morocco and the hustle of the souks and narrow streets of Marrakech also provided participants with a great introduction to their globe-crossing experience.

"Riding through Morocco and completing the first section of the trip was a real highlight – for a lot of the group it was their first time in that part of the world and they were really impressed with the riding and how friendly the locals are," says Kevin. "There are five sections, so completing the first was a milestone. Our second milestone was reaching Ushuaia, Argentina – the most southerly city in the world. It was my seventh time there and it has a special place in my heart and I know for a lot of the riders it was a dream to ride to the ‘end of the world'."

Almost all of those taking part in the epic ride are using BMW GS motorcycles and according to Kevin their performance has been "faultless". "We have a mixture of BMW GS models and the BMW dealer has taken good care of us. We've just had them all serviced and we're ready to start clocking up more miles. Morocco and Patagonia are perfect playgrounds for the GS, and with the whole trip being more than 40,000 miles long (65,000km) it will be a good test for both the bikes and their riders," he says.

Expert planning and years of experience by Kevin and wife Julia, who run Globebusters as a team, mean the mission has all gone smoothly – the only narrowly-avoided hiccup so far came courtesy of one group member who accidentally left his passport at a border crossing. Thankfully, Kevin discovered it purely by chance when filling out a customs form at the same crossing an hour later.

Next on the itinerary for the explorers is the biggest culture shock so far, as they leave behind the European feel of the countries they've visited so far. "We head over the Andes Mountains next, before we enter Bolivia and then Peru. This will be especially interesting for the group, as things really change when we get there. We'll also have altitudes of up to 4,000 m to deal with. We're all excited about what comes next."