Originally Posted by
Scooper
Adding 9mm to the axle-to-crown dimension will change the HTA from 72.5° to 72.3°, which will give you 55.4mm of trail with the 50mm fork rake, so the change from the existing 376mm C-A 45mm rake fork to the 385mm C-A 50mm rake fork will reduce trail by 4mm.
I think your calculations concerning the head angle change are off. I just measured 3 different bikes, this time with a 9mm block and I keep coming up with a .5 to .6 degree change. That measurement seems to be supported by some of the other posters although I don't know the source of their information.
I hope I'm not coming across as argumentative for the sake of arguing. I'm trying to learn as much as I can about what really effects bike handling. I can't trust any sources that originate from the marketing departments at the big bike companies. Most of what they put out to sell their bikes ends up being utter BS.
I'm having to start from scratch here.