I did some zone 2 riding with the Chung method at lunch today. Negligible wind, pretty good day. Data seems pretty good for comparing.
Head “normal” is so a helmet like the Giro would keep the tail out of the wind. “Slammed” is trying to get the head down so I can bite my knuckles on the aerobars.
Below is just relative CdA, not absolute. I’m interested in the delta.
-Giant Pursuit mips road helmet, head “normal”: 0.2623
-POC Cerebel, head “normal”: 0.2524
-Giro Adv 2, head “normal”: 0.2522
-POC Cerebel, head “slammed”: 0.2496
I am not disappointed or surprised the venerable Giro Adv 2 did well against the POC in the head tilt it was designed for. What really surprised me was that the overall “spread” from slowest to fastest was only 0.01 from an aero road helmet to a TT helmet.
Sure, the “jammed” down head was faster with being 0.0127 faster from a road helmet.
Looks like at my power would be 0.7kph or .44mph. About 21sec in a 10mi TT. Extrapolating to 40k, that’d be about 45 sec.
I’ve been doing a little more helmet testing myself lately and was surprised by the results. For years I used an LG Rocket until I decided to test it and found it was no better than my very old LG helmet (not sure the model). I did some research and ended up buying a Specialized TT and did some testing and found it was faster than my old helmet. All well and good. Then one day I decided to test my $30 salad bowl helmet that looks like the first-gen Giro aero road helmet. I could not tease out any difference between that and the Spec TT. I tried one more time and the Spec was slightly faster, but perhaps within the ± of my testing ability.
Still, 45 seconds in a 40K is not bad, though obviously it would probably be lower unless you can ride the whole thing “slammed.” I’m not sure what you expected, but if I could gain 45 seconds (for 40K) from just a helmet I would consider that money well spent. In my testing, the Spec TT may have been a couple of second faster over a five-six minute loop, so maybe 10-15 seconds faster over a 40K. Given that the cheap road helmet is more comfortable and much quieter, I’m not sure what to do with the Spec helmet now.
Thanks for the input. Just felt like the “delta” was less than I’d expect. The old “asshole Lance” TT bike picture of the times gained for equipment I remember the helmet being about a minute over 40k.
Personally, I gain the most speed by a huge margin wearing my skinsuit even over a “team fit” kit. I need to test that one day just for curiosity sake.
Perhaps the road helmet offerings as of 2018 and newer are just “that much better” than road helmets of yesteryear. So the difference is smaller.
I bet if I threw on my "greenway ride with the dog in a basket) helmet that the POC would test light years faster.
I’ve spent my pennies on equipment to be able to tweak my fit and nice wheels…so, maybe peddling some helmets I don’t stick with on Ebay isn’t a bad investment if I find something that gains more watts than wheels. I’m not opposed to blowing $500 on a Tempor and selling the Cerebel for $200 if it tests better. That or an Aerohead Ultimate.
We have a guy on our team with a regular Aerohead. I’ll be testing that next though. Free test before I buy one if it tests well.
I think since I saw that drop in CdA with the slammed head, I need to work on some lowering of the front end of the bike next. I have about 1" of stack left available to remove. I’ve been slowly training myself “down” in stack while holding or gaining a hair of power along the way.
I can hold the head there for a 10 miler. I can also do it if doing sweetspot for around an hour, but not yet full threshold for an hour.
I’ve gotten the watts/CdA reasonable, but I still think I need that “next big thing” in my aero and fit.
Post a picture of you on the bike and I can tell you if either a Met Drone or Tempor is likely to be a good choice.
The one helmet I don’t understand is the Uvex. That looks like it should not be a fast helmet, but I have seen pictures of MTM using one, amongst others that know what they are doing, so there is some there there. I just can’t figure out why it would work.
I don’t know where you are on skinsuits, but those are a pretty good bang for the buck as well.
Post a picture of you on the bike and I can tell you if either a Met Drone or Tempor is likely to be a good choice.
The one helmet I don’t understand is the Uvex. That looks like it should not be a fast helmet, but I have seen pictures of MTM using one, amongst others that know what they are doing, so there is some there there. I just can’t figure out why it would work.
I don’t know where you are on skinsuits, but those are a pretty good bang for the buck as well.
I adjusted fit tonight for about an inch less stack and moved the pads forward to cheat the 10cm rise and get the hands back up. I’ll get new video. Pic I do have is really poor quality.
Old fit video had a bit too much stack for the Tempor. I have to dig to find it.
One helmet I hear crickets on is the hour record holding Adwatt. Seen nada on here.
Post a picture of you on the bike and I can tell you if either a Met Drone or Tempor is likely to be a good choice.
The one helmet I don’t understand is the Uvex. That looks like it should not be a fast helmet, but I have seen pictures of MTM using one, amongst others that know what they are doing, so there is some there there. I just can’t figure out why it would work.
I don’t know where you are on skinsuits, but those are a pretty good bang for the buck as well.
I own a BP 3.3 that I like. Fits like well, body paint.
Here ya go: I can’t roll my hips too much for pics not on a trainer or I’d roll off the stand and fall over!
Thanks for the input. Just felt like the “delta” was less than I’d expect. The old “asshole Lance” TT bike picture of the times gained for equipment I remember the helmet being about a minute over 40k…
…I think since I saw that drop in CdA with the slammed head, I need to work on some lowering of the front end of the bike next.
One thing I’d like to point out is that even when conditions are good and you have good consistency, it’s hard to be certain of your results. Have you analyzed the uncertainty level of your test?
With that caveat…
You could gain a lot or nothing with an aero helmet. .01 seems like quite a lot to me.
I would not assume that the slammed head means you need to lower your bars… rather get good at slamming your head! Lowering your bars will tend to make you reach down with your shoulders and make your head pop up relatively. Make your front end a compact and streamlined unit. You actually want pretty high bars for that. Scrunch. Shoulders forward and in, head down… pivot your neck at the shoulders and lower your face to forearms, and turtle your head to glance up every couple seconds.
Very evident in the last pic that you are reaching with your shoulders. I’d suggest raising your bars a good amount (I went from -18 to -8cm on mine, but that’s extreme), and see if you can get a similar torso angle using different shoulder posture. It could be quite a bit easier to make the front end compact.
Very evident in the last pic that you are reaching with your shoulders. I’d suggest raising your bars a good amount (I went from -18 to -8cm on mine, but that’s extreme), and see if you can get a similar torso angle using different shoulder posture. It could be quite a bit easier to make the front end compact.
I think I understand.
Could I raise front the rest my forearms more on pads than elbows?
Right now I am pretty far forward on the pads. I can sit back some to pull that shoulder reach out.
I agree with Ron, I’d like to see what you looked like with a bit higher stack and perhaps less reach (I know it’s heresy these days) having your nose closer to your knuckles.
I think what part of your arms you rest on the pads is personal preference. I can’t stand riding with anything but my elbows supported, but some guys can ride much further up their forearms (which is sometimes due to “cheating” UCI 10cm… but nevertheless)
also think that POC would look/slot in better if you raised your eye level a bit
I agree with Ron, I’d like to see what you looked like with a bit higher stack and perhaps less reach (I know it’s heresy these days) having your nose closer to your knuckles.
I think what part of your arms you rest on the pads is personal preference. I can’t stand riding with anything but my elbows supported, but some guys can ride much further up their forearms (which is sometimes due to “cheating” UCI 10cm… but nevertheless)
also think that POC would look/slot in better if you raised your eye level a bit
**also also, dry denim will lead to bad chaffing
I appreciate all the input.
This actually sounds like my next aero test. Only takes a few minutes to add spacers.
You all know more than me, but I’m curious to see my data for it.
I used to believe I just had long upper arms… nope! I just have a lot of shoulder mobility and I’d use that the reach the bars with lots of drop. The torso angle defined itself by other constraints… like femur to hip angle. It wasn’t doing me any aero favors, just made me uncomfortable and it was hard to see.
I have to agree that less drop would be a good thing to try. The curvature of your back and the tendency on the first photo to have to look straight down makes me think that you are losing power and will tend to lift your head to look down the road.
As for the Tempor, or other “big†helmet, I think there is a good chance it will work well. Note that your ears are down and aligned with your shoulders. The wings on Tempor will help lift the air over and around your shoulders and more smoothly dump it on your back. My guess is that the BP is not going to be your fastest choice. I think the longer tailed helmets tend to work well with a smooth fabric down the back. The Velotec is very affordable and might be worth a try.
Anyone have any time with both the Tempor and a Met Drone? The drone seems attainable price wise and availability.
Geez the prices on the Tempor. I could sell a spare wheel I never use and cut losses. Just some of the ones for sale make me nervous with international shipping from forum users for those prices.
I’d wait at this point on the Tempor unless you find a slamming deal or know for sure it’s a magic lid for you. POC seem to be maybe possibly releasing a rehash/update, probably the other side of the Olympics, but who knows exactly when. It might bring the prices down to something more reasonable.
The Mistral is another helmet that might work similar.
I found a line on one brand new at something not stupid unreasonable. I’ve wasted more on a wheel before I didn’t end up using. Go figure. I’ll give it a try.
I’ll get it in and test it out. If it works, I’ll sell my other POC and keep my cheaper Giro. The Giro and my existing POC were within a gnat’s ass in my runs of each other. So, I could recoup more on the nicer lid.
I figure if I sell my existing POC if the other one tests better plus a wheel I never use then I’ll break even.
you shouldn’t have any trouble selling the Tempor if it doesn’t work so long as you aren’t paying the very tip of premium. That’s the good thing.
I hope to get all my testing done in mine before prices drop (if they ever do)
Thing is, if there is a re-release…per POC’s own website the initial MSRP on a new POC Cerebel was $350. That’s what they still list that lid at, you can find it used a lot cheaper.
If you’re even remotely in that ballpark then it should be fine.
I don’t doubt they’ll probably re-release something that does it justice, but you can’t be 100% guaranteed it will “fit” that riding position as much if they want to sell more helmets.
Then we’ll see a competing market of “GEN 1” vs. “GEN 2” helmets.
Either way, I’m selling off unused kit to cover my experiment.
Helmets are tough to tease out differences. I did test a few last time I was at A2, but glazed over some I wish I had tested (like the Tempor) but my position has changed enough since then that that data is pretty outdated most likely. Aero eyeball lies unfortunately, but these two might have promise vs. the Aerohead (which was best for me at A2 vs. Bambino, Catlike long tail, S-works McClaren - medium and small - and the Cerebel)
Both helmets that will rip your ears off trying to put on / take off
And…the Tempor is 10w faster at my mortal speeds. Using it out the first time also I like the field of view better than the Cerebel for some reason. Which makes no sense. It is also actually quieter than my Cerebel.
So…for my position and at 300ish watts…saves me 10w over a Cerebel. That was without closing the vents off on the Tempor. Also, in all honesty, the skinsuit I used is probably a small penalty to the Tempor also given the design of the back/shoulders. It was a skinsuit more suited to the Cerebel.
Yeah for good data!
Oh, for the non-mortals like myself…the watt difference for a strong pro would have been way more than 10w faster.
