My wife and I both have hybrids with smooth tires (27 x 1 1/4). I want to get knobby tires for them so we can do some light trail riding. But I can't find any knobby tires in that size, the closest I can find is 27 x 1 3/8. Can I use that size tire with the rims I have?
Are there any other tire sizes I can use? Can I use a 27 x anything or any 630mm tire?