yeah so ideally you would want to experiment, or have a pro fit you, on your current bike until you find a position that you are pretty sure is the one you want. using stems and spacers you will probably be able to do that.
once you get there, you will know what stack and reach is to your elbows, and you will know the stack and reach of your current frame.
*ideally* you will have a flat stem of normal length and no spacers and a really nice aerobar getting you in your position.
So you look for a frame where you won't need a huge stack of spacers, or crazy adjustable aerobar to get your elbows where you want them.
Don't be too picky though, if you find for instance that you need 3cm of spacers to fit on a P4, but a slice would require none at all...still get the p4! (as an example)
for example fitting my wife we started with a cheaper bike and she spent a season using it and figuring out a position she liked. it required a really upturned stem on that bike. So then you just measure from the top of the head tube the vertical and horizontal distance to the end of the stem. You want a frame that will let you use few spacers and a flat stem to get there.
In her case we opted for a 56 P2. No spacers, but she does have to use a pretty short stem still. No way to avoid that without sacrificing DOZENS of grams of drag =)
try a different browser maybe for the stack/reach link?
Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team Aeroweenie.com -Compendium of Aero Data and Knowledge Freelance sports & outdoors writer Kathryn Hunter
