Kilo is correct, tire sizes (widths) are very limited with 21s. 21" tires also cost a lot more than 20s or 22s do. Sometimes you can find a rear 21 tire, but no corresponding front tire that matches it in brand. Less headaches and frustration to stick with 20s or 22s, in my opinion. I replied to Rich's Q via PM, but thanks for the response Kilo. I don't want to be the tire expert here, I only sell forged wheels
