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#132
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New Bontager Helmet Material
On Tuesday, April 2, 2019 at 1:01:25 PM UTC-7, AMuzi wrote:
On 4/2/2019 11:38 AM, wrote: On Thursday, March 28, 2019 at 10:11:15 AM UTC-7, Radey Shouman wrote: writes: On Wednesday, March 27, 2019 at 12:58:43 PM UTC-7, Radey Shouman wrote: sms writes: On 3/25/2019 5:38 PM, John B. Slocomb wrote: On Mon, 25 Mar 2019 sms wrote: On 3/25/2019 3:01 AM, John B. Slocomb wrote: snip more snip I cannot understand why women do not seem to have the ability to think. +1 OTOH they say the same thing about us. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 While women have subjects in where they are much more thoughtful than men, driving through a supermarket parking lot at 25 mph though puddles 3" deep while other people are trying to get their groceries to their cars is not one of them. One was throwing a bow wave the size of a Destroyer Escort. |
#133
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New Bontager Helmet Material
On Tuesday, April 2, 2019 at 11:03:20 PM UTC-7, wrote:
On Tue, 2 Apr 2019 22:11:49 -0400, Frank Krygowski wrote: On 4/2/2019 12:52 PM, wrote: ... They are available in the $150 normal helmet or the $300 MIPS helmet. I do not think that the MIPS would add anything to the helmets but I would have to see test data from Trek before making that judgement. It seems to me that you don't have to worry about the helmet forcing your head to rotate if the deceleration is below a given level. FWIW, Randy Swart - who is probably America's most dedicated promoter of bike helmets - doesn't believe that MIPS is worth having. I'm wondering whether MIPS is really needed. As I read it MIPS is a protection against rapid rotation of the head which ,might cause damage to the brain. https://helmets.org/mips.htm Snell testing reveals no performance gain with MIPS In 2018 the Snell Foundation's Bill Muzzy presented to ASTM's F08.53 subcommittee the results of Snell testing of MIPS performance using a linear impactor and offset (oblique) impacts. Snell tested a MIPS and non-MIPS version of the same Specialized helmet. Their results with full details will be published in a journal soon. https://www.cycleworld.com/mips-is-p...met-protection "MIPS, an acronym for "Multi-directional Impact Protection System", in which a low-friction layer permits 10 - 15mm of sliding action independent of the direction of impact. " Assuming that you hit the ground at, oh lets say, 30 mph, not a super fast speed on a steep hill. Is 10 - 15 mm of movement sufficient to protect your brain? I hit the ground at 30 kph, about 18 mph, and my pelvis broke. I don't believe that 10 - 15mm of sliding movement would have helped a bit. -- cheers, John B. Motorcycle helmets have hard shells and the means by which you fall on motorcycles is in general different from that of how you fall off a bike. If you run into a car head on nothing is going to save you but motorcycle accidents are almost all "slide-outs" and the hard shell really doesn't strike the ground all that hard and the hard shell protects you from asphalt damage to the brain cage. |
#134
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New Bontager Helmet Material
On Wednesday, April 3, 2019 at 12:54:14 PM UTC-7, wrote:
On Tuesday, April 2, 2019 at 12:46:44 PM UTC-7, jbeattie wrote: On Tuesday, April 2, 2019 at 11:29:45 AM UTC-7, Sir Ridesalot wrote: On Tuesday, April 2, 2019 at 12:52:17 PM UTC-4, wrote: On Tuesday, April 2, 2019 at 9:38:32 AM UTC-7, wrote: On Thursday, March 28, 2019 at 10:11:15 AM UTC-7, Radey Shouman wrote: writes: On Wednesday, March 27, 2019 at 12:58:43 PM UTC-7, Radey Shouman wrote: sms writes: On 3/25/2019 5:38 PM, John B. Slocomb wrote: On Mon, 25 Mar 2019 14:51:39 -0700, sms wrote: On 3/25/2019 3:01 AM, John B. Slocomb wrote: snip But strangely no one seems to be particularly upset about the 37,133 highway deaths (2017) or at least I see nothing in the news that says so. You must have missed the mandates for airbags, safety glass, padded dashboards, collapsible steering columns, back-up cameras, seat belts, TPMS, etc. None of these will prevent 100% of deaths or injuries. But each one has some effect, and don't add much cost to a vehicle once in high volume production. Yes, and now that we all have air bags it is discovered that the airbags kill people :-) As for not adding to the cost of the car.... I once tried to cost a sedan without safety belts, no radio, manual shift and hand wind up windows. I found that none of the dealers in Bangkok could quote on such a thing and that while they could be special ordered it had to be for a number of vehicles. Something that a taxi company might do. I did find that 10 units without any modern refinements was substantially cheaper then 10 units with "as usually sold" equipment. Some features actually decrease the cost. I.e. the mechanism for manual windows costs more to manufacture and install than a small motor and switch, so buying a manual window vehicle is probably no longer possible in most places. That's likely true. Designing a door that can accomodate both manual and automatic winders, and designing, manufacturing, and stocking separate interior trim panels for both options is definitely more expensive and involves more engineering tradeoffs than supporting only one option. So if only 0.5% of the market wants manual window winders, *and* they expect them to be cheaper, then they cannot survive. Sometimes it's only in those last few moments, when you're sinking into a pond and your windows refuse to roll down, that you realize how much you wanted manual winders. But more often not. transmission versus the cost of a clutch and associated controls. In the U.S., a manual transmission car may have a slightly lower MSRP than the automatic model (though often the price is the same), but a higher street price because they are not sold in large quantities. -- Though I live all around water and have my whole life, I've never driven into water. One must wonder about the driving characteristics where you are. Neither have I. Usually, when it happens, it's not intended. Yesterday they predicted light mist. As I was going to the supermarket the sky opened up. By the time I got to the store only 1/2 mile away the water in the parking lot was 4" deep and the women drivers were driving through it so fast that people going in and out of the store were being drenched by the bow waves. I cannot understand why women do not seem to have the ability to think. Well, a large percentage of them anyway. None of those doing this were men. On Sunday I stopped in a Trek shop and looked at the Bontrager helmets. The one thing I was interested in was whether or not the helmet had the International Safety Standard approval. I can see where it might not pass the standard but likewise I can see how the actions of the new impact material simply slow the deceleration but as they crush build an increasing deceleration rate as the material is building up in the crush zone. All of my helmets have been throw-aways after a crash so it doesn't matter to me that you have to replace it with much more visible damage to the liner. In the case of the Styrofoam liners they make the helmet with a lot of vents and the Styrofoam which compresses very little will break into the vents using destructive collapse rather than targeted deceleration as the new helmet does. They are available in the $150 normal helmet or the $300 MIPS helmet. I do not think that the MIPS would add anything to the helmets but I would have to see test data from Trek before making that judgement. It seems to me that you don't have to worry about the helmet forcing your head to rotate if the deceleration is below a given level. At $150 and $300 each I can see where the price of helmets would could a family off of bicycling. I don't think that a helmet that starts breaking apart on impact is going to offer much protection in a high speed fall. $300? Yikes. Maybe it would qualify as durable medical equipment subject to payment under a health plan. Get a helmet prescription. -- Jay Beattie. Jay, when was the last time you bought a helmet? https://www.competitivecyclist.com/g...c m8gaGVsbWV0 Now as I was saying, I don't think that MIPS is of any value, so the helmet without MIPS is $150. I bought a new helmet about two and a half years ago, after cartwheeling over my son and breaking my hand. I also broke my helmet. I got a close-out Giro Atmos II from Western Bikeworks for $69.99 -- marked down from full retail of $139.99 (I looked it up on my account page. Damn, I've bought a lot of stuff from them). My son has the top of the line Giro with MIPS, but he got that for super-duper pro deal. Giro is one of those companies with generous pro deals if you happen to be in the industry. I just watch sale tables. -- Jay Beattie. |
#135
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New Bontager Helmet Material
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