Originally Posted by
sggoodri
The "trailer bike" rear-half-bike systems (like my Burley Kazoo) have much, much less drag than the sit-inside two-wheel trailers (like my D'Lite). On the Kazoo, my son is sitting directly behind me, in the draft zone, with minimal added wind resistance. I keep the tire pumped up to maximum to reduce rolling resistance. And, he helps pedal! It's a lot like a tandem in terms of fast cruising speed on level terrain, although braking and steering stability are not as good as with a tandem. You won't accelerate as fast, and you'll want to stay under 25 on downhills, but on a rail trail this shouldn't matter.
The narrower width of the Kazoo also makes passing on greenway/rail trails easier than with the D'Lite.
I don't doubt the efficiency and look forward to riding with one of those in the future. It won't work yet, though. Despite the hefty weight, the little man only just turned three (kid is tall and made of muscle).
Edit: an having seen a Burley Piccolo in person, I want one! It's pretty hilly where we live so the gears would be a great thing to have.