Originally Posted by
Ron_s
In this case it changes the head tube angle. I have not measured the angles, but since all other tube lengths in the front are the same length in both the 71 and the 74, then since the TT length of the 74 is an inch shorter the head tube angle would have to change also.
Certainly, but changing the rake fixes the change in head tube angle to make them ride similarly. And head tube angle is generally changed to vary the wheelbase or reach. It's what prevents massive toe overlap on small bikes and huge wheelbases on tall bikes. But HTAs and TTs aren't changed for handling.