I'm trying to compare the reach of two bikes. I like the fit of Bike A with 52.5cm top tube. I am trying to set up Bike B to fit like Bike A so I need to know what the reach is in relation to the bike that fits me well.

Bike A: 72.5 head tube angle, 75 seat tube angle, 52.5cm top tube
Bike B: 72.0 head tube angle, 73.5 seat tube angle, 53.6cm top tube

I've read that .5 difference of seat tube angle = .5cm of tube tube

There a 1.5 degree difference in seat tube and .5 difference of head tube. Bike B has both slacker angles. Does this mean Bike B has a reach of 51.6cm relative to Bike A???

Any formula that I can use to figure this out?