Ok, got the Schwinn 12 from WM. Installation went okay and the only confusion was which direction to mount the spoke sensor. The pic indicated the magnet to face inwards, but common sense said to make it face the fork mounted receptor. And I tied it as close to the hub as practical as it was said here to maintain balance.
Anyway, I have one question. Should I follow Sheldon Brown's calibration chart or the one in the manual. SB says a 23c should be 2097, but wheel diameter is 26.5" X 25.4 X 3.1416 = 2114. I put in 2117 as it was slightly larger and I did some math computing the difference between a 28c and 32c (19) and between a 25c and 28c (12) and that led me around the same number as a 26.5" tubular in the manual to 2117.
Is that close enough? Maybe, but it is very far from SB's 2097.
That is all.