Originally Posted by
Maelochs
Until then .... if you are finishing second by a few seconds in race after race, go more aero. otherwise, get more fit [...] As far as I know, aero position on the bike is what really matters ... that is where the greatest gains and losses happen.
You can get more fit, improve your position, and use slipperier equipment. You can do all three: the rules allow it.
Otherwise, I wouldn't worry about the .05 aero improvement of anything but a TT helmet
An improvement in aero of 0.05 may sound small but it's huge. That said, going from a "regular" road helmet to an appropriate aero helmet can save you in the neighborhood of 1 sec/km, sometimes more, so in a 40km ride, that's ballpark 40 seconds. For slower riders, a bit more (aero improvements roughly scale evenly across fast and slow riders, but since slow riders are on course longer, their raw absolute time savings are greater).
.... and when you really are high up in the ranks of Triathletes you will be hanging with top-tier triathletes who will likely know the best helmets and the best prices.
Even really really high up in the ranks of triathletes, they don't usually know. Sometimes they know for themselves but they won't know for someone else.
The bike leg of an Oly Tri is 4x longer than the run, so if you're 1 sec/km faster on the bike, that's the equivalent of running about 4 sec/km faster, or about 6 secs/mile. Runners know that improving their pace by 6 secs/mile is actually not a trivial amount. (And you're still allowed to do both).