(apologies for redundant posts: couldn’t find this addressed anywhere)
I’ve done plenty of races in the heat with an aero helmet (Giro), but none in humid conditions. Mostly upper 90s / low 100s here, but fairly dry, as opposed to mid-80s/mid-90s with higher humidity.
I’m getting ready for IMLou I wonder if anyone has advice: good or bad idea to only pack the aero helmet?
Thanks!
I live an hour from Louisville and have never had a problem with the heat+humidity combo, even with the most unventilated aero helmet (LAS). Keep yourself hydrated and nourished and good luck! Watch out for the Volkswagons and 5 eyed fish in the Ohio!
I’d say bad idea… but maybe that’s just for me, I’m A) not that fast. B) get pretty hot in an aero helmet.
I just think the 3-4mins (total guess) you might gain by wearing an Aero helmet you’ll lose much more on the run from over heating.
I’ll wear an aero helmet for sprint tri’s and TT’s but never for an Oly-Iron… but then again, that’s just me and I think I’m over heating when I wear it.
Shanks
What’s the longest ride you’ve done with an aero helmet, holding the aero position?
I was fine with one at the inaugural (and hottest) IMLou (5:29 ride time). Remember, it is only going to save you up to a few mins, so if that doesn’t matter, then by all means, wear the cooler lid!
Longest ride w/ it has been about 100 mi in moderate conditions, didn’t feel any effects at all (and actually liked that it kept more bugs and bees out of my head!). Longest race was a very hot (+100F) half, still no probs. Didn’t use it for IM-CH last year and, of course, it was windy, cold and raining, so it would have been perfect. Such is life…
Leaning toward the non-aero for Lou though - who knows, maybe karma will kick in and it’ll be cold! Ha!
** was fine with one at the inaugural (and hottest) IMLou**
Rod, I’ve been trying to confirm the temp/humidity of IMLou two years ago. I also did the race that year and volunteered last year. Trying to compare the conditions between the two- both were freaking hot.
I have a LG Crono that I am planning to use. It doesn’t have the ear flaps so I get a little more ventilation with it.
Bringing up weather karma: for shame! Are you trying to tempt fate?
I wore mine for the Auburn half last year when it was hot, no difficulty there. Are you preriding the course at all? You might judge based on that. Do you know if Sinclair wear his for China or Korea? Those were undoubtedly hotter.
The worst was the Sat before when it was close to 100 with 80% humidity or whatever. I think I saw 89 during the bike (little hotter during the run), but high 75% or so humidity again.
I’m more concerned about whether or not to wear sunglasses. My Oakleys completely fog up in the morning humidity (live in Louisville). Ever put anti-fog solution on shades? Any suggestions?
I would bring it and wear it as soon as you wake up. It will help you in the 4 am scrum just to hold a place in line. Then it will keep your brains inside your skull as you have the crap kicked out of you with 3,000 other people in the swim. Finally, it might save your life when the redneck with the dualie knocks you off the road.
You can take it off for the run, though. 
Chad
You’ll be fine. Your focus should be on your hydration & fluid management strategy. Having a bottle of water to squirt on your clothing periodically during the ride will do wonders…water goes on the body, not the head (yes I know it feels wonderful but it’s really your core you want to cool, not your head). If you race regularly in your aero helmet you’ll only regret not bringing it to your A race…