I need help understanding backspacing as it pertains to wheels. I'll start out with a few questions.
1. Is 0" backspacing considered to be where the hub face is in the center of the rim?
2. Are there both negative and positive backspacing?
3. Which moves the rim away from the body?
4. How do you measure backspacing on an existing wheel?
5. Do wheel mfg's provide a range of backspacing in their wheels or do you just have to shop around for the backspacing you need?
As you can tell, I am new to this subject so any help/advice will be appreciated.