Originally Posted by
tatfiend
I find it interesting that Schwalbe lists more tire options for 635mm BSD tires than 27" (630mm BSD). In the US at least the 630mm size is a lot more common. Apparently not true in their other markets. Also surprised that the Marathon Plus is not available in 630mm (27") size.
All true. We wish (at the very least) that the Marathon Plus were available in a 630. I'm not sure how common this size is outside the US, but the 635 is commonly used on bikes in India, China and the Netherlands. It's fair to say that if I were responsible for Return on Investment numbers with regard to making tires and tire molds, I'd probably make tires for those markets as well.