Originally Posted by
DaveSSS
I have two frames - one with a 74 STA and one with a 74.5 STA. I have the same seatpost on both bikes, but the saddle is moved further back with the steeper STA, to place the saddle in the same position relative to the BB. Sometimes you can't get a perfect match with reach, since stems only come in 10mm increments. I opted for a 10mm shorter stem on one bike, with saddle a bit further back, to get the same reach.
105mm are fairly common. You need to search a bit more for 95mm and 115mm but both are available.