Originally Posted by dduelin
Can o worms but I say '81-84 twin shock models. You get the 1981 improvements - Brembo brakes, lightened flywheel, Nikasil cylinders, electronic ignition and still have the classic airhead fenders, tank, and side covers.
I'll drink to that. Most affordable would be an R65. I had an R65LS (harder to find now) that I rode all over the country and loved it. R80 is a good choice, but would cost a little more. More torque, but not all that much faster, really.