I changed the front tire on my Valk. I removed a Shinko 777 with 16K earlier than I had to, hadn't hit wear bars and probably had another 2K miles left. I thought I was going on a long ride, didn't pan out. I installed a Shinko 712, 150/70 rear. Got it from Chapmoto for $95 shipped to my door.
Have about 1K miles on it and so far can tell no difference from the 777 front I was running. All good.
I have a Shinko rear tire on the front of my standard, it's been a rock solid tire from day one.. didn't even have to balance it

it's been smooth as silk at any speed.