We tend to TT at a lower cadence on the tandem, than I do on a single bike. Mid 80's on the tsndem, where I would do high 90's myself. I've found that I get more power out of my stoker when she feels more resistence in the pedals. Perhaps with more experience we can raise the cadence, without a dropoff in power from the rear.
I haven't found that the lower cadence changes my HR much, just puts more of a load on my legs.
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