Head Tube Angle?

[oldguy00]

Just wondering, how does head tube angle affect the fit of a bike (reach?)?
I know 1 degree SA = about 1cm in position over the BB. So other than changing the front end handling of the frame, what does the change in HA affect?

I currently ride a frame with:
TT = 55.5
SA = 73
HA = 73

I'm looking at a new frame, with the following:
TT = 54.5
SA = 73.5
HA = 72

I'm assuming the reach on the new frame would be .5cm less based on SA and TT differences, but not sure what the difference in HA makes...

Thx!

[Dave]

The effect of changes to the HTA are far less, on the order of 1-2mm per degree. The pivot point if is HT/ST intersection point. The distance from that point to the stem is much smaller than the distance from the BB center to ST/TT intersection.

The 72 degree HTA will bring the bars a little closer.