Hi Matt999,
A tale of two bikes: shipping and buying
I have done it both ways. In 2012-2013 I rode a BMW F800GS from my home in New Jersey, US through every country in Latin America (except Chile and Paraguay.) The bike was "shipped" on the Stalhratte from Panama to Colombia. The South America portion of the trip was a clockwise circle around the continent for ~6 months. On the back end of the trip the Stalhratte transported myself and bike from Colombia, to Jamaica, Cuba, then Mexico. Not exactly the same as getting a bike from England, but the struggle is certainly similar.
The F800GS was purchased and set-up for this extended Latin America trip. I expected to be riding a fair amount of highway in US, Mexico, Brazil, Argentina and Peru. At 6' 3" tall I added an aftermarket windshield to deflect the wind and rain away from my lumbering size while cruising. A tour seat replaced the more narrow stock seat. Panniers, crash bars, bash plate and hand guards rounded out the customizations. The bike was ridden for 3,000 miles to break it in and surface out of the box issues. (Snob comment: "There were no issues, because I paid for a BMW.") Before leaving I bought spare front and rear tires, so I wouldn't have to struggle to find my ideal tires on the road. I also packed a few spare oil filters in case they proved difficult to find (indeed, the lack of oil filters in stock fo my bike at the BMW dealer in Caracas validated my planning.)
Quirky tip: pack a few bottles of engine oil if you are immediately going to burn a few thousand miles of road. That first oil change will free up space in your luggage! Why? Everyone takes too much stuff, some give things away or ship home, other doggedly bring back all the unnecessary thing originally packed. I love the approach of taking up consuming space before leaving, only to have it available in a few long riding days.
I had a great time over a total of 9 months on my F800GS. The bike fit me perfectly and performed like a champ. This bike was chosen over an F1200GS as it lighter, thus easier to pick up. Yes, you will drop your bike, especially if you plan to ride dirt/gravel roads (and you really should ride off the pavement.) Hopefully all the times you bike goes over will be at low speed...or holding still, yes holding still. The lighter the bike, the easier to pick up. On the 2012-2013 trip I didn't ride much off the tarmac. A little in Guyana, entering Brazil, some in Argentina, a couple of days in Bolivia, that's it. That has changed since buying a 250cc bike in Peru.
How I ended up with a Peruvian Bike
A few years ago friends invited me to join them on a commercial tour in Peru, riding 250cc bikes. The size seemed too small for me, but I'm always up for fun, so I went along. We rode from sea level into the Andes, then tore around the mountains for 7-8 days. What a blast! I was hooked on riding a 250cc bike. Fast forward 2 years, I bought a bike from the tour organizer and took it on a 8 day self guided ride in the Andes. In January 2018 I returned with friends for a 6 day action packed ride (the disadvantages of working full-time.) I'm hoping to go back to Peru again this year for a solo ride. In the fuzzy future I have a planned ride, starting in Peru, a large semi-circle of the Brazilian interior, Paraguay, eastern Bolivia, then back to Peru. Still later I plan to ride the 250cc to Argentina and Chile. Owning a bike in South America is part of my long term adventure riding plan.
Buying & Selling
You might not be thinking about keeping a bike in South America and returning to it over the years. If yours is a one off adventure, then think about the end of the trip and selling the bike. It is the least amount of hassle if you end your trip in the country where you bought the bike. Selling a bike in a different country is possible, but requires more effort to overcome the inevitable issues for the purchaser to import the bike (i.e. pay importion taxes.) Yes, bikes are sold to other travelers and somehow they work out to documents. Other bikes are sold to farmers, stay on the farm and never see a license plate again. Just something to think about.
What to buy?
Get a Chinese 250cc bike. Why? Parts are EVERYWHERE and mechanics are easy to find. The locals all ride Chinese bikes, so go with the flow. Tires will be easy to find as well. I bought a bike that was already ridden for ~1000 miles (I forget exactly how much) which is a really smart move. On the last two trips I was employed full-time and didn't have time to deal with breaking in a new bike. Better to let someone else work through out of the box problems.
Setting up my bike in Peru
My Peruvian bike has a custom metal frame, built at affordable prices by local talent. Welding services are very affordable in South America, so don't worry about buying a luggage frame. I took two small Pelican cases (heavy plastic, waterproof boxes) for panniers. Soft panniers might be you choice. A rubberized duffle bag (Ortlib) goes across the back seat and hangs slightly over the panniers. The last thing I do is wire my GPS to the battery and attach the mount to the handle bars. I am not riding for hours at highway speed, so a windshield is not needed. Hand guards shouldn't be too hard to find and are high recommended to protect both your hands and the levers.
There are a number of motorcycle tour outfits throughout South America that are interested to sell a used bike and keep their fleet up to date. If you have the language skills you can find a bike online (in South America there are online motorcycle sales websites that feature used bikes, in case it didn't occur to you.) My travels introduced me to a tour operator in Peru that sells new and broken in bikes. You can message Charapashanperu here on the HUBB or visit their
website for details. Charapashanperu does a great job of set-up bikes and the price of a Chinese bike makes it all work.
Feel free to send me a private message if you want more details.