With two strong riders, a tandem can be notably faster than a single bike, especially in descending situations. For this reason, many tandems have larger high chainrings such as 54-56 teeth. Our Santana came stock with a 54 tooth outer chainring.
Tandems in general can be slower than single bikes on steep uphills, hence the desire for lower low gears. Our tandem has a 28 tooth small chainring, and we're running a 13-15-17-20-24-29-34 cassette. But most of the time we were in the 44 tooth middle ring.
In our 25+ years of experience, we discovered we're a more of a relaxed team, and we never really used the 54 except very rarely on long straight gradual descents. On steep descents, my dear wife was actuating the drum brake long before we'd get close to spinning the 54 in higher gears. So several years ago I swapped the 54 for a 48, giving me the ability to half-step gearing as needed. This usually means most shifting is on the rear, but then I can choose either the 44 or 48 to fine-tune effort, which is nice when there are two of you working. When switching to a half-step, I did have to swap the MTB front derailleur for a road front in order to not mash the middle ring, though. The 48-13 highest gear lets us pedal to about 24 mph or so, and after that we just coast and enjoy. I suppose I could swap the 28 inner for a 24 now, but so far the 28-34 has been low enough to get us up all our climbs so far.
Last edited by RCMoeur; 05-26-23 at 11:30 AM.