Originally Posted by
TandemGeek
The wheels when looked at by themselves, yes...
However, not so for a tandem that has 1.5x as much aero drag as a single bike. Moreover, unless both riders fall into that physically fit, average size model the entire marketing spin on total bike/rider aero drag reduction is substantially less for a tandem if only because the total aero drag number is substantially higher to begin with....
True, the percentage of drag from the wheels will be lower on a tandem, but the amount of drag coming from the Op's 48 spoke wheels is also going to be a lot more than a conventional 32-36 spoke wheel.
Thus I'm betting the speed increase at 25 mph is still going to be something around .25mph.
Note that I'm not suggesting this a huge increase in speed. For a 40km time trial we're talking about 30 seconds.
And without doing any testing, that small, but measurable speed increase would be consistent with our anecdotal experience.
Originally Posted by
TandemGeek
Moreover, to really reap the moderate reductions in aero drag a team really needs to be pushing their tandem at the higher speeds where aero drag becomes large enough to yield those more tangible reductions.
Note that when I tried to model this, my assumption was with enough power output to produce 25 mph. For those few gifted people that can time trial at 28mph or above it would be more. If you're doing 18 mph it would be a fair amount less.
Originally Posted by
TandemGeek
The only reason I could ever recommend something like racing wheels for a tandem that's not being used for racing is: (a) they look racy, (b) they feel more lively, (c) they're typically lighter than most conventional wheels, (d) they provide a huge placebo effect that can make your team train and ride harder or more often, and (e) you have the cash on hand to buy them as a second set of wheels.
I'd agree with all that. If you're not racing (or doing competitive group rides that are essentially races) then the admittedly small speed increase isn't going to matter much.