These continued to evolve into the early s most noticeably by replacing the act of threading the chinstrap through rings with a quicker to use buckle. Traditional bicycle helmets are designed to be well ventilated and protect for a single higher speed crash only before being replaced. Also, from the UK you have Yakkay brand helmets, which are a basic skateboard style helmet with various soft hat-like coverings. In the late s came improvements in the foam that negated the need for a hard, heavy outer shell.
One of the first, the Bell Ovation, had a soft lightweight shell that was taped to the foam, but more commonly they had no shell at all. Unfortunately in practice these tended to shatter into pieces and scatter at the first impact leaving the user vulnerable to further impacts. Manufacturers experimented with embedding wire mesh, but ultimately returned to soft shells. Early soft-shell bicycle helmet, and three shell-less.
Evolution of taped soft-shell bicycle helmets. The main problem with the band of tape was aesthetic and it could eventually deteriorate so the shell could separate from the foam. In the early s came another innovation: injection molding the foam into the shell, rather than manufacturing them separately and then taping them together. Initially it meant the front strap or strap anchors were exposed, but later on they figured out how to make them recessed. Of course, the trend towards models with more and more vents came out.
In the mean time, an occipital lobe retainer became standard; this is the strap that runs across the back of the head. Later came one-size fits all ring fit systems, where you tighten a fastener on the retainer rather than having multiple sizes of bicycle helmets and further fine-tuning fit by swapping out different thicknesses of pads.
Occipital lobe retainer with ring retention system. I find it works as intended but the elastic it requires makes it feel noticeably tight compared to traditional fit systems. Whether this makes a difference in the real world remains to be seen. Bicycle Helmet with MIPS as well as a front bug net to keep stinging insects from being sucked into the front vents, a feature more common in European bicycle helmets. Probably not. There have been various safety standards at different times and places but there have been no real-world differences noted since the adoption of the ASTM standard in the late s.
If you look online for recommendations; you see the suggestions to chooser white or bright colors to be more visible, or having a rounded shape, or few vents. But does having a bright, visible color make a difference for safety?
It involved motorcyclists, but the same principles presumably apply to bicyclists. A white bicycle helmet as opposed to black is just too subtle to make a difference. History finally begins for the nowadays bicycle helmet and new producers such Pro-Tec, Fastex, Giro, Hopus Technologies emerge. The article is considered to be a mile stone, as it drew the attention of cyclists concerned by their own safety and also an important part in developing various protection standards.
In , Jim Gentes designed an adult helmet which featured ventilations but no shell, and also launched Giro Sport Design, selling the new concept which was a big hit at that time, thanks to its low weight. Sells were good as all the athletes and people who could afford to pay the high price instantly bought the new model. Giro used as an outer cover a very light lycra cloth, manually sewn in the United States.
A small detail, making the whole helmet so expensive…. However, all the EPS helmets that followed afterwards had a major disadvantage: they snapped at the first impact. Pro-Tec tried to compensate this with Mirage, a helmet which featured nylon mesh inserted into the foam, in order to reinforce the whole assembly.
Ventilations were clearly visible and many companies followed this design by using the same technique of inner reinforcing sustaining the foam and not allowing it crack. The next big design step followed in with the introduction of a very light shell covering the EPS, as we can see in the photo on the right.
This was the model which quickly managed to conquer the market. Outer shell and EPS were separately produced and then glued together. Another innovation followed in the beginning of the s thanks to a new manufacturing procedure which actually allowed molding the foam on the outer shell. Thus, helmets became more compact, without any gaps, allowing companies to produce even more protective helmets for the same thickness. Designers could play also, as helmets became more attractive, nicely streamlined and featuring more vents.
This is another mile stone to be kept in mind and after all this history talk we must also say the most efficient shape for a helmet in the unfortunate event of a crash is the one of a bowling ball. We have ranted against the trend, but without much effect, and have been unable to get provisions in any standard requiring low sliding resistance.
We could only hope the fashion will reverse as fashions always do, and lead us back to smoother designs. Finally in there were signs of at least a few rounder, smoother designs produced for the "commuter helmet" niche in the market. Bell introduced the Metro, followed quickly by a number of others.
The Metro was an intentionally clunky design, but SixSixOne found a design in China shortly thereafter and brought the helmet on the right below, the Allride, to the US market. Weak marketing doomed it to low sales, and the company dropped it from their line after But the original producer brought it back for as the Vcan VCK37 on left below. The manufacturer advertises it as a more aerodynamic design based on automotive research.
Track racers in the UK were early adopters and their demand alone led to backorders for the helmet. It is not clear why the aerodynamic claim led buyers to reject all of the aero research of manufacturers of the elongated designs.
The extreme of the elongated aerodynamic style is the chrono helmet developed in the 's for Olympic time trials. This one has a rounded front and usually has a very long tail that rests on the riders back when in the tuck position used by time trial riders.
Vents are minimal or non-existent. Early models had only a shell without impact protection, but in Louis Garneau introduced one that met the requirements of the US CPSC standard, and various manufacturers soon began making them to the European CEN standard.
We have a page up on current chrono helmets. Another major helmet shape that crept into bicycle helmets is the "skate-shaped" helmet. Originally developed for skateboarders by Pro-Tec, the style has lower rear coverage, small round vents in the front and even smaller round vents in a circle on top. The skate style helmet is almost always a hard shell with ABS plastic. Although originally using a squishy rebounding foam that provided the multi-impact performance needed for aggessive skateboarding, the helmets evolved into bicycle helmets because the squishy foam would not perform in harder impacts called out by bicycle helmet standards.
After when the CPSC standard came into effect, big-box retailers were not willing to put a helmet on the floor that could be bought as a bike helmet but did not meet the CPSC standard.
As a result, most skateboarders now are buying single-crash bike helmets with crushable EPS foam inside. A few manufacturers are making helmets with EPP foam or other foam that can be certified to both the ASTM skateboard helmet standard and the bicycle helmet standard. Liners Until the 21st century, bicycle helmet liners were all crushable foams.
In the late 80's or early 90's came the introduction of new foam types to replace the simple EPS picnic cooler foam that dates from the 's. It is extensively used in the automobile industry. EPP has the desirable characteristic of slow return to its original shape after an impact, and is therefore well suited to multi-impact helmets. It is generally considered to have slightly more rebound on initial impact than EPS, and a little less impact attenuation for a given thickness.
Although Aria Sonics had an EPP helmet for five years or more, the design was never appreciated by consumers, and its marketing was inadequate to establish its advantages. A Canadian company called Headstart introduced EPP designs in the mid's, but the helmets were not well finished and did not have the quality appearance that was required to sell in the U.
Although GE had not originally designed its combination foam and resin product for bicycle helmets, it was appreciated for its resistance to catastrophic failure, permitting manufacturers to open up larger vents and thin out liners in some places. This is a slightly heavier foam with exceptionally small and uniform cells.
It skins over in the mold, producing a shell-like cover on the lower section below the regular plastic shell. EPU can be inmolded or the shell can be applied afterwards. It has almost no rebound and performs well in lab tests. Taiwanese manufacturers are the main users of EPU, and helmets made of it are among those on the Snell B certification list, indicating that they perform well indeed. There may be some environmental issues related to the production process for EPU, however.
In a ski helmet company known as Team Wendy or W Helmets showed a new helmet with a foam they call Zorbium. The company claims it has extraordinary energy management capabilities, with a "rate-sensitive" quality that makes it give in a lesser impact but causes it to stiffen to handle a harder hit. Although the concept is apparently sound, we never could get any test data on production models. The foam is heavy and absorbs sweat readily.
W Helmets remains the only user of this foam, and their implementation has been directed toward ski models. By they were no longer making civilian helmets. It may seem surprising that most bicycle helmets are still made of the EPS developed in the 's. Over the years we have heard of various experimental foams that were about to break open the market with astounding performance characteristics, but few have materialized in actual production, and their benefits are not readily apparent.
There are probably limits to such properties as foam thickness. Basic laws of physics make it evident that it would be very difficult to stop a rider's head from 14 MPH to 0 MPH in less than, say, a half inch of crush space, without exceeding the , or g limits in bicycle helmet standards. So better foam may not produce much improvement unless the crush rate of the EPS has some undesirable characteristics or multi impact is important for the sport. Thicker helmets could do more, but consumers reject them.
Some attempts have been made to improve the way EPS works, mostly with dual-density formulations. The cone-head technology developed by Don Morgan and marketed in is designed to make the transition between layers smoother. In the years since several newer foams have appeared, associated with marketing labels like "Brock foam," or "cross-linked foam. Beginning about with Cascade lacrosse helmets, liners appeared that were not foam-based.
Most depend on plastic constructs of some kind that manage energy by collapsing on impact. They showed up first in football and lacrosse helmets, but in there were production bike helmets with Koroyd [tm] liners that look like bundles of soda straws. They still had EPS molded around them. Non-foam liners have huge potential for future development. They produce custom helmets with a 3D printed liner of hexagonal honeycomb cells that crush on impact.
The interior liner is custom made for the wearer's head, using data from a head scan done with an iPad or iPhone that can be done at home.
HEXR claims their helmet provides better energy management than a foam helmet, but cites only one European standard lab test at an average of g, a level that is good but can be attained with a good standard thick EPS foam liner. In theory, a custom helmet can use all of the available space between your individual head and the inside of the shell for energy-management liner, so this technique could be the future of high-end helmets.
For uniquely shaped heads or those with cochlear implants that alone could be a big advance. The easily-managed head scan raises the possibility that manufacturers of conventional off-the-shelf helmets could match individual head scans done at home or in a shop with the interior dimensions of their helmets to provide best fit recommendations at a fraction of the price of a custom helmet.
For those who must buy online that could be a big advance. We have a page up on helmet liners if you want more detail. In the late 's other materials including polypropylene replaced some of the nylon, but the resultant strap is difficult to distinguish from nylon.
Each formulation has its own characteristics, affecting such parameters as buckle slippage. The first fasteners were mostly D-rings, a design borrowed from motorcycle helmets where the strap is fed through two d-shaped rings and doubled back through them to grip.
This is done each time the helmet is put on. Making the rings from stainless steel ensures resistance to corrosion from sweat. This design is simple, very strong, reliable for a decade or more of use and ensures that the rider can achieve optimum tightness on every wearing. But many bicycle riders find it fussy and sometimes difficult to fasten, and triathletes complain that it takes two hands.
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