My needs are simple: I want the best fit I can get and the best tread design/compound for all around use at a reasonable price. The field really gets cut down on the sizing issue alone. Only Metzler and Continental have stepped up and offered a fitment recommendation for our 500/550 wheels:
Front WM1 rim – 1.85” ID = 3.25/19
Rear WM2 rim – 2.15” ID = 4.00/18 (Honda says 3.5/18 and 3.75/18 for 500 and 550 respectively)
I know allot of folks are damn happy with the 100/90-19 and 110/90-18 combination and a light search will turn up a mountain of fine tires in those sizes. But, the fact remains that just about every data sheet indicates the 100/90 is recommended for a 2.15” rim. Granted, I’m very limited in experience with motorcycles but I’m real convinced that standing up the side walls at a precise angle is
real important in road racing tires for formula cars. The 100/90 is close for sure but in my book it’s a second choice if a precise 3.25” is available. As for the rear – well, we just don’t have a choice since a match to the front in 3.5” or 3.75” tire in a 18” rim just isn’t out there.
After running up and down the tire sheets and reading the poop on all the neat Spitfires, Battleaxes, Venoms, TT100s, K491s et al the list gets chopped down pretty quick on sizing alone:
Metzeler Lasertec 3.25-19M/CTL 54H and 4.00-18M 64V reads real good as an all around tire and is current with latest compound
Conti Super Twin TK22RC and TK44RC reads like a possible contender but no retailer carries the TK44 rear?

Conti Blitz TKH23 and TKH24 reads like a nice soft, sticky tire but perhaps wanting in wet weather.
Avon RoadRider AM26 I asked about here. Looks very interesting – Brit wet weather experience, very current compound and a sheet that reads right down my alley for everyday use.
FWIW, I’m leaning to the Avon and Metzeler as a consequence.....