rruff wrote:
tri_yoda wrote:
Any frame can be made lighter (no matter what the material) to an extent, its just a matter of trade offs. I said "claimed" benefit (in the sense that you can't really substantiate such a claim
Good proven aluminum frame designs come in at <1100g. And they are cheap. Bossi are claiming 1500-1550g for this Ti frame.
Not really clear what your point is? Are you claiming no one could ever build a Ti frame that weighs less than an Al one? I agree with you that in general, you can build lighter frames with Aluminum, but that's not an absolute, depends on what your overall design objective is. For example, Al has a fatigue life, for most bicycle applications Ti is above the endurance limit; if you were trying to build a 50,000 mile touring frame I am not sure the aluminum would be lighter than Titanium.
Good proven carbon are coming in at 800g these days. You also need to be really careful about claimed weight, what size frames (are they comparable?), is it frame only, frame and fork. People play all kinds of games when quoting weight.