The entire Virago line from the 250 up to the 1100 was a pretty solid motorcycle. They did make a 1000 in 85 by the way. Like most bikes, they have a few common problems. The starter clutches were a weak point, but they can be repaired fairly easily. The carbs are standard Mikuni and are pretty simple to overhaul, although they are a pain in the ass to get off. There are a few tricks that will help and pay close attention to the hoses and lines that go to the carbs and air filter boxes. Most parts are still available from Yamaha and reasonably priced. There's a few forums covering all the Viragos, but they're no where near as good as this one. If the rest of the bike is in good condition, clean tank and not much rust, it's probably worth $500, not a whole lot more.
.....Paul
