120-18 looks correct to me, but keep in mind that (believe it or not) different manufacturers and/or model tires labled the same size actually vary in width - some by a bunch. Also, 120-18 may look correct to me because for about 20 years or so I used 130-18 tires on the rear. They are a big pain to mount on the stock (narrow) rims and they do not handle any better than the 120 size because the tire profile is distorted from being pinched on the narrow rim. I wouldn't even consider 110 on the rear - too narrow. The 120 size works really well. on the KZ650 rim. Ed
1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
