What do u ride now?
Helmet field testing? CdA impact
- Thread starter ed72
- Start date
Balor
Zen MBB Master
You can have your MBB *and* hamster bars, in fact Nik Vatin a giving away one for free:
http://recumbents.com/forums/topic.asp?TOPIC_ID=7124
If you don't find low-speed behaviour too much to your liking, you can install a strong return-to-center spring to counteract flop.
I had already decided that long tiller and narrow bars would not work for me but I do hope to regain better arm, shoulder, and neck function. I thought long and hard about my limits. It seems obvious to me that the ability to pull on the bars adds significant W' power. Climbing is my weakness on a bent but it is what it is. I am fairly certain to have a V20 one day. In the meantime, I am finding "free" speed aerodynamically.
When I get the helmet testing done, I'll share the results.
http://cruzbike.com/forum/threads/ready-to-build-the-ultimate-vendetta-racing-machine.8105/page-2
When I get the helmet testing done, I'll share the results.
http://cruzbike.com/forum/threads/ready-to-build-the-ultimate-vendetta-racing-machine.8105/page-2
Balor
Zen MBB Master
This is not free though, my hands get very tired after a couple of hours and I even get nasty back spasms sometimes when I try to maintain it (TT mode), really viable only for burst efforts (maybe I should hit the gym...). "Spinning" also works, but seems less effective mechanically than pushing (provided you push while effectively braced, and not though a layer of lard, *sigh*).
My next avenue of research is shoulder boosters. "Bridging" (same principle - moving bracing points to bonier regions of your anatomy) works for a lot of people (me as well) - but it is also very hard to maintain for a longer period and negatively impact your handling.
Shoulder boosters like on hour record highracers should allow one to use shoulders for bracing indefinitely, especially if you combine it with pulling and spinning.
Not to wander too far astray but I "think" more power is delivered to the road when I brace not against my derriere but against my lower lumbar or sacrum area on the flats. Just watching the power meter type of anecdotes but it is quite analogous to sitting up straight climbing a steep hill on an upright, more power displayed. I'm 6'3'' and 220 but should be 180, so, there is some absorbing material aka stored energy south of the sacrum. When I lowered my seat to 18-18.5 degrees from 20.5-21 degrees, I expected to lose power. I lost none in my assessment. I also noticed that less weight was on my butt and a certain freeing of that area and a more natural pedal motion (unconstrained psosas). A study would be nice but who is going to do it and why? How one holds the thorax and shoulder during climbing impacts breathing. Do I have proof? No. But, there are a lot of muscles involved in breathing and has anyone ever seen an opera singer lay down and sing? I'm also improving lung function in the reclined position using powerlung device and a variety of different training regimens to not only enhance muscle recruitment but to also enable mitochondrial development and Type II a/b muscle conversion. Of course these are very controversial but in the absence of good studies and clear guidance, one must forge ahead with trial and error.
I am going to spring for a Giro Vanguish and compare it to my other two helmets........0.18 mph increase would be nice!
I am going to spring for a Giro Vanguish and compare it to my other two helmets........0.18 mph increase would be nice!
I did buy a Giro Vanguish. It is cooler than the Bell Star. I have not had a calm day when also free, so, no CdA yet.
I did my weekly training 10 mile TT. I used the Giro Vanguish and also took off the Zipp 404 front wheel running 25 mm GP4SKii and replaced with a Flo 60 Carbon running 23mm Supersonic. Chopped 21 seconds off my personal best with 2 more watts average power. So, not easy to say how much the helmet helped, yet. It was 91F and I think the better cooling was also a big factor because 21 seconds is a massive improvement in time. I have been gaining 2 seconds here, 5 seconds there, and sometimes a little slower. I'll get some real numbers on the helmet eventually but it looks like a keeper, just for the better cooling alone. This is 0.5 mph faster......maybe 0.18 of it is the helmet??
I did my weekly training 10 mile TT. I used the Giro Vanguish and also took off the Zipp 404 front wheel running 25 mm GP4SKii and replaced with a Flo 60 Carbon running 23mm Supersonic. Chopped 21 seconds off my personal best with 2 more watts average power. So, not easy to say how much the helmet helped, yet. It was 91F and I think the better cooling was also a big factor because 21 seconds is a massive improvement in time. I have been gaining 2 seconds here, 5 seconds there, and sometimes a little slower. I'll get some real numbers on the helmet eventually but it looks like a keeper, just for the better cooling alone. This is 0.5 mph faster......maybe 0.18 of it is the helmet??
I tried to put Smiths under them but they would not fit. The shield gets pretty close to my cheek. The straps also tuck my ears in.....TMI.
I use eyewear under the Bell Star.....mostly for rain and bugs hitting my eyeballs. I also tape over the shield about at the horizon or tree level to block the sun. A layer of blue painters tape on the inside for contrast similarity to the sky. I suspect the Giro will block rain sufficiently.
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Mathew Fy
GRU
I can fit all my glasses under the Vanquish shield with room to spare. Note that my wide nose pushes the glasses up high. These are the largest pair I have.
Just to close the loop on this thread. I have done testing comparing the Bell Star to the Giro Vanquish. Helmet airflow is highly individual and needs to be taken into consideration. I am definately faster using the Giro and it is cooler. It is worth testing if someone is looking for CdA gains. It might not be faster on another rider. I decided not to post the actual CdA gains because of the variability but it is a keeper for me back to back testing. Marginal gains of a handful of watts here and there eventually add up.
Good luck to all Cruz racers.
Good luck to all Cruz racers.
How much cooler is Vanquish from Bell Star? A little or a lot? I feel my head is burning if it's above 75 deg outside.
I'd say it was 60% between the Bell Star and my Lazer Z1 MIPS. I like the Lazer, too. It also fits properly against my neck rest. I also have the Specialized Evade and prefer the Vanquish.
I feel as if air is flowing over my head with the Vanquish and with little hair to impede, evaporative cooling is enhanced compared to the Bell.
I Chung tested the Vanquish with the face shield vs Vanquish using just my cycling eyewear.
The faceshield was run twice on a calm day. I was surprised to find 0.004-6 lower CdA using glasses. Shocked actually. So much so that I'm going to repeat the testing on another day.
I was testing because the lettering on the shield is directly into my field of vision and it drives me out of my mind more than usual. I was interested to see the "penalty" to ripping it off and going with just glasses. The shield is nice for blocking sun and rain......
Not that anyone really cares but if my testing is repeatable, this is a huge freebie
The faceshield was run twice on a calm day. I was surprised to find 0.004-6 lower CdA using glasses. Shocked actually. So much so that I'm going to repeat the testing on another day.
I was testing because the lettering on the shield is directly into my field of vision and it drives me out of my mind more than usual. I was interested to see the "penalty" to ripping it off and going with just glasses. The shield is nice for blocking sun and rain......
Not that anyone really cares but if my testing is repeatable, this is a huge freebie
Osiris
Zen MBB Master
Over the past few weeks I've been trying out a new breathing technique. I remembered that my Scuba instructor told us to always exhale and inhale completely to maximize the amount of time you get out of your air tank. He explained that taking shallower breaths is inefficient because it just moves a lot of CO2 back and forth without expelling it from the lungs. Previously on hard efforts, I'd run out of oxygen before my legs ran out of energy. Invariably I'd be gasping for air at the end, and it was that rather than muscle fatigue which would limit my efforts. Breathing more slowly but making sure to completely exhale and inhale has made a significant difference, and it shows up in my Strava times. Now it's my leg muscles that are the limiting factor. I no longer cross the finish line seeing stars and feeling like I'm about to pass out from oxygen
deprivation, and I can maintain sub-maximum speeds for much longer. Obviously some of this is simply due to my legs getting stronger, but I can now maintain the same speed over a two mile segment that only a couple of years ago would have been my limit on a one mile segment. It's impossible to say how much of that is due to my new breathing technique, but I notice that I'm no longer seeing a massive power drop near the end, which is where I'd always run out of breath. On Friday I was able to average ~32 mph for nearly a mile when I was already tired, which would have been unimaginable before.
I had similar conclusions as you last year. I kept coming back to why threshold and O2/CO2 movement and perfusion in supine position can throw a lot of curveballs. Balor and I went back on forth on PM for many months on this. Some of what you found out seems partly related to changes in perfusion in the supine position IIRC. Breathing rate and depth were a couple of key learning for me, it is different or maybe I should say more critical than on an upright. It is easy to get CO2 out of wack but I actually think in the other direction. It is also very easy to constrict the thorax, relaxation is essential; otherwise, breathing is constricted and also of note, the muscles associated with breathing would take additional oxygen for them to function and I believe there is a centrally mediated sympathetic nervous system response that impacts peripheral (legs) perfusion (O2 into and CO2 out of the mitrochondria, which are already compromised from a partial pressure sense due to their positioning (compared to an upright). I was considering designing my own seat, that is how convinced I was. LOL. Tensing the shoulders and bracing is anathema to aerobic FTP development; however, throw that comment out the window for anaerobic efforts. Aerobic power (time trials or long distance riding) must come from the pelvis; the seat must be long and comfortable.....shoulder/arm positioning is also important for respiration. Getting the O2 up and into the mitochondria. Age, endothelial elasticity, NO, Anyways......
It sounds like your threshold has moved up considerably. Congrats.
I had had a hard time trying to determine the limit of aerobic power on a bent and getting there. Is the lungs/heart or is the legs. I am pretty sure it is both and several factors for each. Too much to go into. Besides we are all unique snowflakes, I just texted the FDA Commissioner......all clinical trials have been stopped because we are all built differently. LOL.
My threshold is finally very close to my old upright days and maybe equal, have not done an FTP test in about 6 weeks for some reasons. 2 years and something like 25,000 miles to call a truce. How many ex-DF riders can actually say and prove that!! I can.
Osiris
Zen MBB Master
The Casco helmet I got from Phil is certainly an improvement over my road bike helmets, probably accounting for a 0.5 mph increase in top speed. However, it's not without problems. When lying back on the M1, the bottom edge of the visor interferes with my view, and there's a sizable gap between the edge of the visor and my face, which is letting a lot of air come in and creating drag. A helmet with a longer visor should solve both problems. Aurelian Bonneteau must have tested many helmets before attempting his world record run, so I looked closely at a couple of photos of him. Here he's wearing as a Casco Speed time trial helmet:
No idea what they cost because I haven't yet managed to find a US distributor who sells them, but when I do, this may be my next equipment upgrade.
No idea what they cost because I haven't yet managed to find a US distributor who sells them, but when I do, this may be my next equipment upgrade.
$500 when I was looking but.....that was 14-18 months ago. I think there is a newer version available. Larry's testing was good enough for me in terms of speed but the close fit of the shield is too much a liability for a lowly randonneur like me.
I was intending to retest helmets with and without visor today but had to take care of my MIL with Alzheimers. I have large and also a medium Giro Vanguish. One of them will get modified with an attached mirror and tons of reflective tape. I need to replace the Bell Star, after 25k miles, it is ruined.
http://www.casco-helmets.co.uk/Casco-SPEEDtime
I was intending to retest helmets with and without visor today but had to take care of my MIL with Alzheimers. I have large and also a medium Giro Vanguish. One of them will get modified with an attached mirror and tons of reflective tape. I need to replace the Bell Star, after 25k miles, it is ruined.
http://www.casco-helmets.co.uk/Casco-SPEEDtime
