Originally Posted by
ppg677
Wait, doesn't a steeper seat tube angle put you more forward on the bike (like a Tri bike), which makes the "effective" top tube length shorter than the actual?
Yeah, maybe I'll just dump those 8-speed Record wheels and hold onto both frames for a bit. 8-speed seems like kind of a no-mans land. At that point friction gets a bit too difficult and 8-speed indexed shifters (or Ergos) are harder to find.
Depends on how you set up the saddle in relation to the bottom bracket. If you use the same saddle and crank length and have found your position in relation to the BB, then the variation in seat tube angle will push the effective top tube length forward of the BB "vertical line" longer on a steeper seat tubed machine. On the noted bikes you have here, maybe 8-10 mm. If you let the seat tube set your position, then no, the Trek will have you farther behind the bottom bracket.
I like 8 speed but I have two bikes, some parts and spares. I would not start from scratch right now unless it started with a full bike.