They will work. 406 is the ISO diameter of the rim and 1.5, 1.75, 2.125 and so on are all 406's. Just watch you don't buy 1-1/2" even though 1.5 equals 1-1/2. When it comes to tires, fractions and decimals don't mix. Our race bikes use 1-1/4" and 1-3/8" tires. They are totally different.