rivrgazr

Thanks, Crankycrank, this was actually the solution I had in mind; I knew the 10 speed 5700 shifter wouldn't mix with the 11 speed cassette. Some people misunderstood me there. It does leave the problem of potential mismatch between the levers' pull ratio and brake calipers, but I have a bike now with older Tiagra 9 speed levers with even older Sora calipers, where I never thought of mismatch in pull ratio, but, braking seems just fine!! Even if it was a problem, this will be a new build, so getting the right calipers isn't really an issue. However, it seems there's some disagreement among respondents on whether or not the 11 speed cassette will go on the 8/9/10 hub. One reply said that machining off the back of the 11 cassette to reduce some width will make it work. This suggests to me that there interference between the back of the cassette and the spokes. Another commented that the machining is not necessary if the cassette has larger inner cogs. Having no first hand knowledge of the matter, these comments together make sense to me, I get the reasoning, just not sure I want to go that crazy to make things work. I really wouldn't want to have to take each cassette to a machine shop to put it in a milling machine and shave off a few thousandths, but I do have a 6 X 48" belt sander that I've done some crude machining with quite successfully, so I wonder about that. Thanks to everyone for the input on this.