Nine athletes tested - 5 men and 4 women. 28oz bottle and a 1.5 liter regular Crystal Geyser water bottle from the grocery store. Link to the YouTube video is down in my signature, but here are the results:
Note: Weights are combined athlete and all equipment. Watts are based on race pace for each individual athlete.
Tony - 180cm, 83.1 kg
28oz Bottle (high on chest) = 2.31% drop in drag / 6 watts28oz bottle (low on belly) = .46% drop in drag / 1.2 watts1.5 Liter bottle = 6.02% drop in drag / 15.6 watts3 liter Camelbak bladder only = 4.17% drop in drag / 10.8 wattsCamelbak bladder + 28oz bottle stacked (see video) = 8.8% drop in drag / 22.9 wattsMeagan - 172cm, 74 kg
28oz bottle = 2.31% drop in drag / 3.9 watts1.5 liter bottle = 5.56% drop in drag / 9.4 wattsKristi - 167cm, 69.7kg
28oz bottle = 3.19% / 5.7 watts1.5 liter bottle = 1.59% / 2.9 wattsAdam - 170cm, 86.2kg
28oz bottle = 4.7% / 11.8 watts1.5 liter bottle = 8.55 / 21.4You can erohighperformance.com to see the rest of the data (click on Aero Data in the main menu) as I’m too lazy to post it all, but the results are similar.
Obviously interesting results. Keeping the bottles high on the chest is key even though it may pull down the neck line. Unless it’s a low neck line, in which case it’ll kill you, which is covered in the video when we tested an athlete who came after our testing for this was complete. I questioned the results, but they were consistent and gel with what others are finding around the world. In fact, I’ve been jokingly asked to stop giving away secrets.
Keep in mind this is real world testing using an AeroLab sensor. We’re measuring the differences as they’re happening. For instance, Adam was going ~ 1km faster for the same power output and wind conditions with his drag savings. Impressive.
Other notes: The 28 oz bottle was empty, and the 1.5 liter bottle was about 1/3 way full (or 2/3 the way empty depending on your demeanor). All athletes tested at their race pace wattage.
Aero socks and calf sleeves are next. I wouldn’t expect the same consistency in the results from that testing, but we may have found an interesting correlation for those who see a drag savings and those who don’t. Oh, and we have a newly released aero shoe we’re testing next week! Stay tuned.
Excellent stuff Jim. Thanks for your contributions as always.
My wife and I went somewhat down this rabbit hole a few years ago. Post pregnancy, the added space up top dropped her CdA, which got me into testing different ways of adding things up top to shape the air and fill in some space on myself. It was quite effective for me in the end too. I ended up with implants. In all seriousness, I never tried stacking anything on top of the Camelbak so that will be interesting to test again.
Thanks. I can’t seem to get it to work so I just posted the main website address and when you click on Aero Data in the main menu it should take you there. That part of the site is still under construction, so I’m sure I have some setting wrong somewhere.
Anyone know how to post a YouTube link? I can’t seem to get that to work either.
Excellent stuff Jim. Thanks for your contributions as always.
My wife and I went somewhat down this rabbit hole a few years ago. Post pregnancy, the added space up top dropped her CdA, which got me into testing different ways of adding things up top to shape the air and fill in some space on myself. It was quite effective for me in the end too. I ended up with implants. In all seriousness, I never tried stacking anything on top of the Camelbak so that will be interesting to test again.
So many rabbit holes to go down, so little time to explore them all.
Thanks. I can’t seem to get it to work so I just posted the main website address and when you click on Aero Data in the main menu it should take you there. That part of the site is still under construction, so I’m sure I have some setting wrong somewhere.
Anyone know how to post a YouTube link? I can’t seem to get that to work either.
I believe you need to specify your site cookie choices using the option boxes at the bottom of your screen before you can post YT links.
21 watts for a rider in the slightly upright position for a 1.5L bottle!!!
That’s literally insane. I’m def one of those more-upright riders that still manages to go fast (for me, at least) in that slightly more upright position where the bottle tested better. I’m gonna have to get one of these and test it myself…
21 watts for a rider in the slightly upright position for a 1.5L bottle!!!
That’s literally insane. I’m def one of those more-upright riders that still manages to go fast (for me, at least) in that slightly more upright position where the bottle tested better. I’m gonna have to get one of these and test it myself…
Yeah, if someone told me ahead of time we’d see those kind of results, I would’ve laughed. In fact, there’s a gentleman on this forum who posted a 12 watt gain, and I almost pushed back thinking there’s no way. I’ve since learned of nearly identical results from others who’ve tested and have been seen using similar bottles in races. I’ve received a few messages today from those same people who now want to try larger bottles. LOL. We did want to try a 2 liter bottle for fun, but never got around to it.
Once you really look at it, it makes sense that 1.there’d be a decent drop in drag, and 2. that a more upright position could be better for this sort of thing. In the end, it’s the shape of the kit that’s created which is directing air around the chest instead of into it. For fun, we’ll test it on a road position in the next few weeks.
Intersting results given the huge drag chutes the bottles are making with the gap/opening beating created at the neck line…
Yeah, I thought so too, but when you take a good look, the athlete’s chins are blocking that air, so it never really gets directed into that location anyway. Outside of our testing, I had an athlete test very poorly with bottles, the first to test poorly actually, and it was because the neckline of his kit was very low, and the bottles did open it up too much causing him to be scooping air.
I really don’t want to start stuffing bottles down my trisuit. I hope these are banned by the rules to keep things simple.
I agree! I was hoping that it was a negligible gain, so that I wouldn’t feel pressured to look silly while on the bike. But 5-24w is too much to pass up on, so I guess I’m stuck doing it until they change the rules!
21 watts for a rider in the slightly upright position for a 1.5L bottle!!!
That’s literally insane. I’m def one of those more-upright riders that still manages to go fast (for me, at least) in that slightly more upright position where the bottle tested better. I’m gonna have to get one of these and test it myself…
Yeah, if someone told me ahead of time we’d see those kind of results, I would’ve laughed. In fact, there’s a gentleman on this forum who posted a 12 watt gain, and I almost pushed back thinking there’s no way. I’ve since learned of nearly identical results from others who’ve tested and have been seen using similar bottles in races. I’ve received a few messages today from those same people who now want to try larger bottles. LOL. We did want to try a 2 liter bottle for fun, but never got around to it.
Once you really look at it, it makes sense that 1.there’d be a decent drop in drag, and 2. that a more upright position could be better for this sort of thing. In the end, it’s the shape of the kit that’s created which is directing air around the chest instead of into it. For fun, we’ll test it on a road position in the next few weeks.
Rabbit hole?
How about the infinite testing now if changing position to more our right WITH 1.5 or even 2 liter bottle increases watt output as well as ERO gains
I’m sure you are way ahead of me in thinking this
21 watts for a rider in the slightly upright position for a 1.5L bottle!!!
That’s literally insane. I’m def one of those more-upright riders that still manages to go fast (for me, at least) in that slightly more upright position where the bottle tested better. I’m gonna have to get one of these and test it myself…
Yeah, if someone told me ahead of time we’d see those kind of results, I would’ve laughed. In fact, there’s a gentleman on this forum who posted a 12 watt gain, and I almost pushed back thinking there’s no way. I’ve since learned of nearly identical results from others who’ve tested and have been seen using similar bottles in races. I’ve received a few messages today from those same people who now want to try larger bottles. LOL. We did want to try a 2 liter bottle for fun, but never got around to it.
Once you really look at it, it makes sense that 1.there’d be a decent drop in drag, and 2. that a more upright position could be better for this sort of thing. In the end, it’s the shape of the kit that’s created which is directing air around the chest instead of into it. For fun, we’ll test it on a road position in the next few weeks.
Rabbit hole?
How about the infinite testing now if changing position to more our right WITH 1.5 or even 2 liter bottle increases watt output as well as ERO gains
I’m sure you are way ahead of me in thinking this
Yeah, I’m losing hair as I type just thinking about it.
After Kona I decided that if I ever did that race again I would start with a frozen bottle or bladder in my shirt just for cooling purposes. But these test results make me want to do it for everything. I have a sprint race this weekend, not sure If I’ll try it there or wait until Boulder 70.3 the next week.
Other notes: The 28 oz bottle was empty, and the 1.5 liter bottle was about 1/3 way full (or 2/3 the way empty depending on your demeanor). All athletes tested at their race pace wattage.
Why was there water in the big bottle? Why no fully empty?
I really don’t want to start stuffing bottles down my trisuit. I hope these are banned by the rules to keep things simple.
+1
People stuffing 90% empty bottles down their suits (that they are not going to drink from) for the aero gains are basically just using fairings. It’s already getting ridiculous, with Joe Skipper putting the kitchen sink down his suit.
Again, many thanks to Jim for doing the testing and video to keep us all in the know.
