Originally Posted by mcatano
Gear inches are really only useful as a rough, relative measure (ie, comparing ratio to ratio), so it doesn't really matter that you're getting slightly different measurements. Measuring by gear inches also fails to take crank length into account.
i thought gear inches was how far the bike travelled with one revolution of the chain ring. i can see how wheel size would make a difference, but whether or not you have 165mm's or 175mm's should'nt affect the revolution of the chainring. it's still only going around once.
am i wrong or am i wrong?