Originally Posted by
Burton
So we're down to 'significant cost' of upgrading an older bike basically. So let me put this on the table for thought. Tires, tubes, cables, bar-tape and brake pads are expendables. Eventually they have to be replaced. Same for cassettes, drive chains, bottom brackets and chainrings. The component cost and installation costs are identical regardless of the age of the frame they're going on.
Until the point at which the components themselves disappear, or your frame doesn't support the latest replacement. This won't happen in 5 years, but it might happen in 10 or 15 years. Rear drop-out spacing may change (again), brake technology might change (think: disc brakes on mountain bikes), chain width may change (think: 11 speeds), steerer diameter might change (think: 1.5"), wheel sizes may become obsolete (think: 27"), etc. If you plan to own a frame for more than 10-15 years, you should also plan to stock-pile enough consumables and spare parts to keep you supplied for the last 5-15 years of riding...
'Aero' components are only an advantage over 40km/h and usually weigh more. Their main application (outside styling) is in TT events and solo riders on closed tracks.
If you had
any experience riding a modern aero road bike (ex: Cervelo S-series) into a head wind, I don't think you'd be saying this... FYI, the commonly accepted belief is that aerodynamic components provide benefit at
any speed and that they provide
significant benefits starting around 18mph (29kph).
Todays high end bicycle frames are slightly lighter than high end frames 20 years back, but not necessarily stiffer or stronger.
You're seriously out of touch: my current road bike is 6lbs lighter than the bike it replaced (16lbs vs 22lbs). The new frame is
significantly stiffer than the old one. As an example, the new bike doesn't feel like a wet noodle when sprinting uphill. And that's after only 15 years of change (1994 vs 2009).