You might want to check out the Kymco Downtown 300 - when they come to America this Fall. The wife and I rode two-up on a demo ride at Mid-Ohio Vintage days last weekend and it was very stable and had enough pep for two-up.
2001 HD XL1200S
1977 Vespa + 1985 Honda Elite
"Man whoever came up with Ronald McDonald was dropping some serious acid.." - SpoonKiller / tiotalruckus.com