This discussion has to take place here. Other Motorcycles sights don't know squat about sidecars. The Darkside post do not understand Sidecar rigs do not steer or handle anything like a Motorcycle. I ride my stuff. 20 to 50,000 miles a year. Tres wear faster on sidecar rigs.
Our newest sidecar is a breast. meaning big , it handles great does all it should right. A 2017 Harley Road Glide Ultra with Hannigan Twin Classic attached. The sidecar come from Hannigan with a car tire on it. It works fine .
The RGU rear factory tire is a 180/65B16 I run Dunlop Elites and on a two wheel bike they wear great and are outstanding. With the sidecar they do fine but you know they will wear right down the center faster . Three car tires are close to the factory size.
205/55R16 is .3 shorter and 1 inch wider Will fit depending on who you ask ?
195/55R16 is .8 shorter and .6 wider will fit according to anyone you ask.
195/60R16 Same height and .6 wider should fit .
The 195/60R16 seems prefect for the rear of the bike. Not all tire manufactures make every size tire. currently I am looking at a SP Sport 5000 Symmetrical. this is the only 195/60 R16 Dunlop offers. I would consider a run flat type tire, and am open to other brands.
If anyone has something to offer I am listening. Plenty of time new tire on the bike now and winter is on the way.
I like this new one. So much that it may stay on the bike all of the time, I have others with 2 wheels to ride.