does that mean my KH20 07 is a 19" uni? why is it called a kh20? :S
Because the effective diameter is 20". The bike industry labels rims by what the effective diameter would be if the rim had a 2" wide tire on it. So 20" rims are really 16" in diameter and 19" rims are really 15" in diameter. You can't find a 2" wide tire that fits a 19" rim, they only have 2.5" wide tires, so to "simplify" things (confuse noobies) people just call wheels with either 20" rims or 19" rims 20" wheels.
Because the effective diameter is 20". The bike industry labels rims by what the effective diameter would be if the rim had a 2" wide tire on it. So 20" rims are really 16" in diameter and 19" rims are really 15" in diameter. You can't find a 2" wide tire that fits a 19" rim, they only have 2.5" wide tires, so to "simplify" things (confuse noobies) people just call wheels with either 20" rims or 19" rims 20" wheels.