is this the right rear tire?

[pa23driver]

So i've owned a CB750 (mag wheels), V-Max, and a Road Star - all of which had pretty wide rear tires. I ordered a new rear tire for my 77 XS650D, which has the spoked 18 inch rim in the rear, the tire size is 4.00 - 18. I went on the cheap this season and just bought the vintage dunlop ($60 on bike bandit), as my bike budget is nearing its end for this project. I just received this thing in the mail this morning, and i could've swore they sent me a front tire, is the rear tire supposed to be this thin or did i order the wrong tire?

 

[XSLeo]

Yes the 18" rear is very narrow compared to new bikes. In metric terms a 110/90-18. The swing arm won't take a much bibber tire. A 120/90-18 a or a 120/80 -18 sometimes fits without rubbing.
What it says on the side wall is the width when mounted on the wheel and inflated. Tires quite often measure less when not inflated.
Some of those Dunlops can be used on either front or rear. Look at the directions arrows, mount it right and you'll be fine.

 

[pa23driver]

sounds good, thanks for the reply