Just mounted a pair of Road Classics on a '95 RT:

Front - 90/90 x 18, $143.14

Rear - 120/90 x 18, $180.03

I have about a thousand miles on them now, and the biggest change is the slowing down of the steering I'm seeing from the Pilot Activs that were on there. IOW, it takes more effort at the handlebar to initiate a turn at speed. The Pilot Activs were the same sizes, and had a very neutral feel. I'm a bit disappointed that these Road Classics do not. Haven't gone far enough to comment on mileage, but I'm hoping for at least 6K miles out of the rear, and twice that on the front.

Here's an update on the Michelin Road Classic tires I'm running on a '95 R100RT. At this point they've accumulated about 3400 miles, and my initial impression holds true. It's a very stable tire at speed, but it requires significantly more handlebar effort to initiate and terminate turns. This is true whether riding with empty luggage or with full bags and a duffle packed with camping gear. I've tried to improve this by running the tire pressures up to 38F and 40R, but have seen no improvement. The rear tire is just beginning to square off, which makes the problem even worse. At this point I'm not inclined to put another set of the Road Classics on, and would welcome any suggestions for a replacement.

I ride a 78 with a 19” front wheel, so my choices are more limited, I would imagine.  When I lived in Kentucky, I went to BMW of the Tri-State in Cincinnati for tires (great dealership, long gone, due to a divorce … too bad).  Anyway, they got me hooked on Dunlop D404’s. Old technology. I think they are just fine, track very nicely, last as long as anything else, and are an awesome value. The last pair I bought (back in March) was $186.  I use sizes 100/90-19 and 120/90-18.