Originally Posted by genejockey

I always had problems with trying to use a plumb bob, so instead what I do is to set the rear tire against a wall, with the bars as near to level as possible. Then I measure from the BB center to the wall and the floor, and then do all my other measurements to the wall and floor and subtract as needed. I made up an Excel spreadsheet that does all the calculations for me.

Saddle height to BB center is the exception. For that, I measure from the BB to a mark the bottom of a small board placed on top of the saddle (because the saddle dips in the middle) which is always placed so the mark is at the same place on the saddle. Sounds complex I know, but in practice it's pretty straightforward.