Umm yeah you're completely sane, there's plenty of people who've done it, 2 up, on smaller than 250. It's not the easiest ride in the world, especially with two on a smallish bike. Do you have much riding experience?

If you're looking to buy in Peru you should speak to charapashanperu

Horizons Unlimited - The HUBB - Horizons Unlimited - The HUBB

He'll be able to give you the complete picture for Peru, and what kind of bikes at what prices are available.

Also work out a route and when you'll be going. For instance I arrived in Santiago in winter and headed north. Stupid. I should have started in Colombia with the warm weather and headed down to Ushuaia during summer, now I need to fly back down after selling my bike in Colombia and get another for going south when the weather warms up. So try and consider which places you want to visit, and work the route out. Starting in Lima if you want to visit barranquilla AND Ushuaia for instance wouldn't work out.

Bike wise, I think you should keep an eye on the for sale section on here, might give you an idea of what else is available where. Ie there are some good foreign bikes being sold all over sur America on here, and usually people advertise months ahead of the sale date. Personally (this is only my opinion) I think buying a foreign plated bike is easier and all round a better option. Ie an American bike (most common). If necessary, transfering the plates to your name is very easy (google overland Title services) or alternatively many people just ride on a "Poder". Some don't agree with me and like I said it's only my opinion.

Another option might be to do a loop from Peru and back to Peru (or Santiago for that matter) and have the place you bought the bike from "buyback" the bike. Not uncommon. And as to the actual brand of bike, take your pick if it's Chinese there's hundreds all similar, zongshen have a decent reputation but not so cheap.

Well, that's plenty for now I think. Good luck, Dan