Essentially the test was this:

1. Athlete's original position is significantly lower than the Plasma Premium will allow with the Tri stem.
2. The TT stem does a good job of matching the athlete's fit coordinates, but disallows the use of the integrated hydration & nutrition set up.

The question we wanted to answer was which would be faster: Athlete's best position using the TT stem without the integration hydration, or less optimal position, but use the integrated hydration we believed would lower the bike's drag? In other words, how much would the drag gap close by using the integrated hydration?

The numbers were interesting, and a little surprising, though I don't want to be deceptive; position trumps everything else! Still I wonder if anyone has Plasma Premium numbers they'd like to share, whether it's wind tunnel, velodrome, or outdoor VE testing regarding the integrated hydration system both installed and removed from the bike in the tri set up? I realize that's pretty specific, but I've never seen any numbers posted, and there might be a good reason why. Anyone care to help out?

Edit: Numbers and photos now posted...



Run #1 - With Front Hydration (including bento and straw): .2721
Run #2 - Remove Front Hydration & bento: .2702
Run #3 - Re-Do Run #1 .2719
Run #4 - Re-Do #2 .2692

Straw could be having some effect, but I've tested straws in the tunnel and on the velodrome so many times and they just don't seem to show up in the results with an athlete on the bike. The top of the hydration system could be disrupting airflow a bit. Much cleaner over the stem without it.

Additional:

Lower position with TT stem: .2580
LG P09 v. Rudy Project Wing 57: .2490

Yep, big difference in helmets, but to be fair, we used a med P09 which is a bit small for the athlete, so a large would likely be a watt or two slower. Still, not surprising. Friends don't let friends use Wing 57's; at least without testing first.

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Jim Manton / ERO Sports