Can anyone cite any studies done on the aerodynamic advantages between different aero helmets? Someone told me a certain company’s aero helmet provided little to no aerodynamic benefit. (I would rather not mention the name, because it would only perpuate a rumor at this point). I have done some Google searching for tests done, but have found nothing. I’m interested in seeing what helmets might be better than others, or if there is any difference at all.
Thanks in advance.
Let me say what I’ve heard to spur things the. Rudy is supposedly no better than a taped helmet.
However, if I were to pick any aero helmet for my needs right now and in the future, I’d go Rudy. It apears to have a small frontal area, the tail that is there stays fairly low, and the earwings may or may not increase effectiveness.
Currently I have a LG prologue and it took a lot of time working with the pads and straps to get it into a compromise between aero, comfort and safety. I would be highly surprised to find out it is faster than a Rudy but its way more comfortable.
Rudy is supposedly no better than a taped helmet.
If a taped helmet is a significant improvement then the Rudy seems like a pretty good deal long term. Granted you could continually tape and retape a road helmet, but considering how much people spend on aero wheels a little for a Rudy seems cheap to avoid the taping.
I guess that just opens the new question of how beneficial is taping a helmet.
Someone posted some comments from MIT about wind tunnel testing. I guess the jist of it was that an aero helmet is more advantageous than aero wheels. Hence all the talk about aero helmets.
Not knowing any better I have to wonder why Michellie Jones, Chris McCormack, and Heather Fuhr would use the Syton helmet, knowing they have all been in the San Diego tunnel recently, unless the helmet was effective. Could Rudy’s sponsorship really be so great they would ignore the data?
However, if I were to pick any aero helmet for my needs right now and in the future, I’d go Rudy. It apears to have…
But, isn’t the whole point of Jim’s post, “Anybody got data?” Without data, “appears to have…” is just guessing.
I know of one guy who tested an LG Rocket vs. LG Chrono and the Rocket was materially faster. Lots of people have tested Rocket vs. regular helmet and the Rocket wins every time I’m aware of. I can’t think of a specific reference to the Rudy. However, if we resort to the “appears…” sort of analysis, it would appear to me that I’d rather have a Rocket (or Giro or Bell) than a Rudy.
Jim, head over to Biketechreview.com and post your question there. Somebody might have a specific reference for you.
Could Rudy’s sponsorship really be so great they would ignore the data?
Yes.
Who says they even took other helmets into the tunnel?
I’m not writing this to say that the Rudy is slow – just that people shouldn’t take too much out of a pro’s equipment choices. Some of those folks ride tires that are proven – proven – to be slower than other tires. Same with wheels, frames and damned near anything else.
I have read a study done by Kaï Hundertmarck (former pro-cyclist and usual top bike times on IM) related in the german triathlon magazine. He was riding on a track at 30mph (controled by SRM) and using different wheels, helmets, an frame (Soloïst and P3). The only things I remember is that the gain of the aero helmet was 6W on a total of around 350 watt. Also the most efficiently wheels combination was a pair of Xentis, before a Zipp 404 + disc. It can be explain by the fact that on a track there is no wind, just a only frontal resistance … the natural incident wind would have shown the disc superiority.
HTH
Nick
Can anyone cite any studies done on the aerodynamic advantages between different aero helmets?
Somewhere I should still have all the helmet test results from Project 96. However, they are >10 y old now, and none of the helmets that were tested are still being made (although you can occassionally find one on, e.g., eBay, and they do remain legal, at least for USCF racing). So, these data are probably not of much use to you, except to illustrate that the right aero helmet can reduce drag significantly (especially the long-tailed ones).
Who says they even took other helmets into the tunnel?
I’m not writing this to say that the Rudy is slow – just that people shouldn’t take too much out of a pro’s equipment choices. Some of those folks ride tires that are proven – proven – to be slower than other tires. Same with wheels, frames and damned near anything else.
You are right and I know/knew it. In the absence of any real data I just have to hope that those 3 people who went to the tunnel and wear the same aero helmet tested said helmet for it’s aerodynamic properties. Seems like not much of a stretch, but as you point out, Pro’s make stranger choices. Until there is real data for the Syton (that is available to me) that is all I have to go on. Not very scientific, but a reasonable rationalization for the time being.
Until there is real data for the Syton (that is available to me) that is all I have to go on. Not very scientific, but a reasonable rationalization for the time being.
I’m sure there is data for the Syton. I’ve seen tunnel pics of riders with and without one, so I assume they tested the helmet versus a regular lid (which is what the pictures show). I just wouldn’t assume that they tested a series of aero helmets from different manufacturers.
I have no doubts that the Syton is faster than a regular bike helmet.
I think Jordan Rapp has an article on the Timex site about aero helmets and specifically mentions the Rudy (presumably a sponsor?).
I am sure they are faster but I just can’t convice myself to get one. I am afraid some old school dude will pass me and laugh. That is what I am going to do if I pass someone with an aero helmet 
That is what I am going to do if I pass someone with an aero helmet
Was that you laughing at me a while back?
Remember, the point of all this aero gear and positioning stuff is not to compare your new result to the guy next to you, it’s to compare it to how you would have done without it.
In my case, getting my bike fit sorted out, using race wheels (808 front and cover on the rear), and an aero helmet took me from needing 240 watts to go 23 mph to only needing about 205-210. Sure, plenty of people can still beat me, but I’m beating a lot more of them than I used to.
In the last two years at Oceanside, I had faster bike splits than guys who I know for a fact are phenomenally stronger cyclists than me.
I am afraid some old school dude will pass me and laugh. That is what I am going to do if I pass someone with an aero helmet
Giggling madly for 15 minutes at my last Oly would have had a negative impact on my bike split.
First disclaimer, I’m not doing helmets or selling helmets for anybody. I just have that problem of curiosity and because I still position a lot of racers I needed to know some facts. I went to the A&M tunnel on August 1st, got a volunteer to test some things and here are the results. Note**** helmets test a little different on different riders because of back shapes and pelvis rotation. These results are for this rider but I think they generally would have the same results.
The bike was a New Look TT frame, FSA aerobars, 50mm Blackwell wheels front and rear. Wheels were spinning, rider was 6’2" - 170 lbs, multi-time Ironman racer, Mark Miller, owns a bike shop in lafayette, La. He supplied most of the helmets, Mark has been to the tunnel with me many times and knows how to sit accurately and repeatable.
First run for base line in his current race position with an untapped Giro Atmos helmet, rear water bottle cages.
Yaw 0 2.5 5 10 15 20
untaped Atmos @ race angle 7.64 7.75 7.41 7.47 7.56 8.33
taped vents Atmos @ same race angle 7.47 7.12 7.31 7.10 7.73 8.16
L. Gar. rocket, tail up 6.97 7.24 7.21 7.26 7.00 7.16
L. Gar. Rocket tail dn 7.24 6.95 7.03 7.03 7.28 7.73
Bell/ Walmart Impulse, taped 7.27 7.63 7.36 7.27 7.38 7.98
Rudy Syton w/flaps 7.31 7.50 7.29 7.07 7.31 7.74
Rudy Syton No flaps 7.24 7.34 7.33 7.18 7.28 7.81
For me, same setup as test #2 - taped vents, Atmos - Landis High hands replicated pretty close: 7.89 7.73 7.62 7.53 7.58 7.97
I’ll stick with lower hands for a little longer.
Andrew Coggan can figure the speed/time for you for fun.
John, thanks for posting this data. Can anyone interpret this data into relative watt or time savings?
John…did I read in this data that the Rocket Tail up is quicker than the Rocket Tail down? Is this like all those short airfoils that stick upright out of the fuselage of many commercial and fighter aircraft to keep the airflow laminar?
John…did I read in this data that the Rocket Tail up is quicker than the Rocket Tail down? Is this like all those short airfoils that stick upright out of the fuselage of many commercial and fighter aircraft to keep the airflow laminar?
Notice, that was only @ zero yaw, or 15-20 degrees…almost no one is ever @ zero, and I don’t know about you, but some basic trig means that at 20 degrees of yaw, I’m probably not riding my TT bike…
Also, factor in the Cda of actually moving the helmet up and down (since tail-up means you can’t see anything), and tail-down seems like the winner.
I’ve seen tunnel video on Willet’s site that show the effects of moving the helmet around, and even if “tail up” were faster, the act of getting it there is pretty messy from an aero standpoint.
Those numbers seem to make a good arguement for the Rocket…
I think that when the tail was up it helped mask the rear water bottles on this rider by shooting the air past the rear bottles before it reattached. If you notice, most of the numbers shot up from 20* and on but I didn’t list the further out numbers. I believe this was from the rear bottles in most cases adding a lot of surface area suddenly.
John, thanks for posting this data. Can anyone interpret this data into relative watt or time savings?
It looks like @ 28mph for 40K, the saving of the Rocket vs. regular/untaped helmet, at 5-10 mph variable wind, 20 degree angle, comes to almost a 2 minute savings…someone feel free to check my calcs on analyticcycling.com, but that seems about right to me.