Originally Posted by
dougmc
More expensive, if you have to buy a GPS, I can agree with. (Not that tape measures are free, of course.) Beyond that, "hugely more work" ? "incredibly complicated method" ? No way. It does have a trivial formula to use, but you had "convert that rollout into the units your computer expects" so it's not like a calculator wouldn't be used in either case. (I guess we could factor in the price of a calculator too.)
Nope, I roll my wheel out once, I have a tape measure that has MM on the tape.
The procedure is really simple. I use the valve stem for the tire marker. Stretch out tape, sit on bike, roll one revolution, read tape, enter read measurement into computer. Done. It is that simple.