I could have posted my question in any one of several forums, but thought I would try the near-senior citizen forum first My wife and I are in our mid-60's and returned to cycling last year after a 20 year hiatus. We have a tandem (and singles) which we are enjoying tremendously having done 3-4 100K and a few centuries. We're getting stronger, but in order to enjoy the centuries available to us in California we've got to be able to climb 10% grades at 4-5 mph without going anerobic. Our lowest gear is 24-30 and I'm reluctant to go larger in the rear because the 13-30 9 spd cassette works really well for us. Given our weight and the weight of the tandem this corresponds to a power output in the neighborhood of 2-2.5 W/kg. Is this feasible for fit seniors? 8% is probably the steepest sustained grade, but 10% is not uncommon.

Right now there is no practical, affordable means to measure power on our tandem, but I'm thinking about a Powertap wheel that will fit both of our singles which would let us measure individual power.