Originally Posted by
Velognome
^^^ Weren't the slack frame angles to help with tracking on rough pavement? If so, steeper angles would have only been seen as useful on prepared tracks, the slack angles would have been better on the rough roads of the period ( pure speculation on my part of course)
For the head angle, I will accept that. For the seat angle, parts availability? The effort to place the seat forward of the seat tube by use of seat posts with forward extensions was common. I will even admit there must have been some suspension to doing that. But why on a track bike even? Granted there are some examples of machines with steeper angles, they seem to appear first on "6 day" bikes, but it seemed to take a long time to filter down to less specialized bikes.