Carretera Austral in Chile is easily in the top five most stunning roads in South America. Mostly gravel and graded dirt, it winds along the Andes through the pristine landscapes of Southern Patagonia. Turquoise blue lakes, ultimate solitude, and windswept valleys dotted with local haciendas - Carretera Austral is an ADV riding paradise to anyone on two wheels. Fuel and lodging is available in most villages and towns; Coyhaique can be a bit touristy, but Puerto Rio Tranquilo and Chaiten reman immune to mass tourism and hordes of gringos as it's so remote.
Riding a small bike was a blessing on the Carretera Austral because you do need to go slow to take the primal beauty and vastness of Patagonia in. Most riders choose the more popular - and more touristy - Ruta 40 on the Argentinean side, so most of the time, you're on your own on the road, which for me was just perfect. Camping is allowed everywhere, and wild camping is ideal at the lakes; there are a few campsites with shower facilities on the way (the lake waters are icy cold) as well as a few small guesthouses and hostels in the villages.
Definitely recommended, and will definitely do it again before it's paved!