Originally Posted by
VegasJen
Fair enough. I know the wheels on that bike are quite light and that's a large portion of the weight right there.
Yes, that probably makes it apples and oranges. A stock Y-Foil lists as just under 19lb while the more standard Trek 5000 series with the same components lists at about 18lb. Those weights were decent for the time.
I'm quite sure you can get a tri bike for around that same cost. Weight wouldn't be my main concern in a triathlon or time trial bike. Get the right geometry (the Y Foil has a more laid back seat tube angle than you'd usually want on a tri bike, for example) and make it as aero as you can. 105 or even Tiagra are fine working components, and there are budget aero wheels out there that work great for a couple hundred grams more.