I'm running that size rear rim on my Tracy, with a Avon 130/80 AM 26 Roadrider
You can see pics in the vote for the bike of the month
If you're running stock swing arm will probably have to modify brake stabilizer bar and custom or no chain guard, but I like the way it looks.
I'm running a 2.15 x 19 on the front with a 100/90 x 19, if I had to do it all over again I'd do what you're doing and go to 18 on the front, just because it gives you a lot more options for tires 😀