Originally Posted by
johnnyboy1
Measured along the top of the chain or the bottom. Or does it matter?
It's the same. It's a question of total slack. The surest way to be sure is to hold the rear wheel and make sure you can transfer visible slack from one side to the other. I think the 1/2" figure is way too much, and the goal is minimum slack but enough that there's still visible slack at the tightest point in the crank's rotation.