The stock size tires for the R3T are: Front- 150/80 16; Rear- 180/70 16.
Avon makes tires in these sizes in both radial and bias ply if I remember correctly. If there is an R in front of the tire size, the tire is a radial.
Generally speaking, you will want to have the same kind of tire on both the front & rear. There are some who say they can be mixed, but I can’t remember which goes on the front and which goes on the rear. I am sure someone will come along and clarify.
I certainly can confirm they outlast Metzlers twice over. Mets that were on the bike originally lasted 7000Km. I'm trying to get 20000 Km out of the Bstones. Roads here in and around Montreal are pretty much flat so they are wearing down the middle and nothing else. Twisties are for holidays on the open road in the mountains. That's next months project, doing the tour of the maritimes ( east coast Canada ).