The longer reach is mandated by the steeper seat angle. That steeper angle puts the rider way forward and that consumes a lot of reach. With the rider further forward less of the cockpit is behind the BB. It's a shift of distance from the effective top tube to reach.
You can't really compare a 2018 bike's reach with one from 2015 with a 73' seat angle. Go ride one and see for yourself.
I had a bike that was 490/74 and it was fine. Then I tried a bike that was 500/76 and it was too small - like, knees hitting the bar too small. Then I went to 535/77 and life is good again.
I agree that some of these seat tube lengths are getting a bit crazy short, but that's just my long inseam talking.
March 6, 2019, 9:10 a.m. - Cr4w
The longer reach is mandated by the steeper seat angle. That steeper angle puts the rider way forward and that consumes a lot of reach. With the rider further forward less of the cockpit is behind the BB. It's a shift of distance from the effective top tube to reach. You can't really compare a 2018 bike's reach with one from 2015 with a 73' seat angle. Go ride one and see for yourself. I had a bike that was 490/74 and it was fine. Then I tried a bike that was 500/76 and it was too small - like, knees hitting the bar too small. Then I went to 535/77 and life is good again. I agree that some of these seat tube lengths are getting a bit crazy short, but that's just my long inseam talking.