Originally Posted by Tom Bombadil
Will, what I'm seriously contemplating is a hybrid of a different design. No suspension but with carbon fork, seat stays, and seat post. Then put on tires with some width and cushioning, like 700x35 with around 65-70 psi in them.
I've tried this type of bike out and it seems to absorb the shock pretty well - between the tires and the cf pieces. The advantage is that this config is about 5-7 pounds lighter.
The lightest bike of this type is the Trek 7.9 FX, which is an all-carbon frame. Comes standard with 700x32 tires. Ultegra-level components. But the list is $2400, I've seen them selling for as low as $1700, but that's not common. The 7.7 FX is one of the carbon fork/stays/post designs.
So instead of your combo of narrower, high-pressure tires paired with suspension on an aluminum frame, these use the shock absorption of larger, lower-pressure tires paired with carbon fiber. My rides have shown them to not quite as smooth as the suspension hybrids on gravel trails, but provide a reasonably smooth ride. And they would certainly be faster, with the reduced weight along with elimination of the energy-absorbing suspension.
Tom- If comfort is your goal, the bigger tires will cushion you. I have CF fork on an Aluminum Frame bike. That does not make for a smooth ride.
Warning: If speed is your concern this idea of yours will not work. High pressure narrow tires make a big difference. I did this now on a Tandem going from 45 mm (50 PSI) down to 38 mm (80 PSI) and the Trek Hybrid from 38 mm (80 PSI) to 28 mm (120 PSI).
I am seeing at least a 10% faster speed on both bikes. (probably more than that)
Weight of the bike is less important on the flats. It will show some effect on acceleration but also not that much. Wisconsin has no real hills. The 3% inclines will not make that much difference.
There is another argument to do away with the shocks: For very agressive biking, the shocks will absorb energy. Some Cyclocross type bikes come without shocks for that reason. But they are build for harsh racing and not comfort. I have looked at these for speed but have no illusion that they are comfortable.