September 23, 2009

comparison of ECE 22-05 and SNELL M2010

As I mentioned before, DOT, ECE , and SNELL are measured with different approaches. Here, i would like to talk about differences between the ECE 22-05 and SNELL M2010 requirements.

SNELL M2010 requires for instance that any location above the test line is to be tested by two consecutive impacts, while ECE 22-05 requires a single impact only to specific points on the test headform. This makes the total impact energy transferred to each test location by the SNELL M2010 standard, almost twice as high as is the case with the ECE 22-05 tests in some consumer size ranges.

In addition, SNELL M2010 impact absorption tests are carried out with hemispherical and bar anvils. Both anvils are known as harsh to the outer shell performance. Furthermore, to insure the helmet shell is strong enough, shell penetration testing is also required by SNELL M2010, but is missing in the ECE 22-05 standards.

King of Helmet - Arai RX-7 GP

Arai took this technology and incorporated it into a brand new helmet that is a completely new design. RX-7 GP is a completely new, developed to be the ultimate racing helmet.

Just take one look at it and you know it is different. Readily recognizable by the adjustable Air Wing spoiler on the back.

The all-new Arai RX-7 GP is the most extensive race tested helmet ever. This successor to the legendary RX-7 Corsair, has been developed in actual MotoGP and Grand Prix races. Tested at high speeds on the straights of international racetracks. Designed for and used by winning professional riders. The result is the stunning new RX-7 GP with an adjustable Air Wing that significantly reduces buffeting and drag when the riders emerge from a full tuck when braking from high speeds, enhancing concentration. At the same time the Air Wing increases the top speed thanks to the improved aerodynamic properties of the new RX-7 GP.

The RX-7 GP benefits from a wider visor aperture that offers more view through the bends, giving you every time that split-second advantage accelerating out of corners.

The RX-7 GP is the very first motorcycle helmet offering the ‘'Peripherally Belted'' SNC outer shell construction, that surpasses even the incredible strength and stiffness of the Corsair shell.

The ‘'Emergency Release'' cheek pads offer increased personal safety in case of an accident, while the famous SNC net material has become stronger to keep the shell shape intact even under extremely heavy loads and impacts.

A new diffuser, larger visor, wider vision, less buffeting, improved ventilation, the list of improvements and industry-firsts is impressively long.

Personally, I believe that RX7 is one of the best helmets on the market right now for bike racing, but it is more suitable to Asian head, as i feel. I prefer to have a lighter but bigger shell helmet.

September 19, 2009

HOW A MOTORCYCLE HELMET IS DESIGNED?

HELMET DESIGN STAGES

A: HELMET DESIGN STAGE


During this stage, the design of a helmet is created under consideration of the required functions, easy handling and an attractive helmet appearance via computer software such as Autocad. This makes sure the helmet can provide comfort and security to users. The success of the design stage depends on the commitment and expertise of the design team.

B: WIND TUNNEL


After the initial design is created via a long process and discussion, the first sample will be made for air-circulation testing. During a test ride, the rider's head – protected by the helmet – naturally travels through the air at the same speed as the motorcycle is traveling on the road, i.e. at speeds of between 20 and over 100 km/h. A large but invisible air stream is thus created around the helmet. The controlled tests conducted with the help of the wind tunnel form a part of the development process.

C: ROAD TEST RIDE

All newly developed models that have successfully passed the design and wind-tunnel stages described above are subjected to a test ride. This ensures that the required functions can be provided in practice. Depending on the price category of the helmet and its specific properties, the conditions in which it is used can differ greatly. For this reason, the test ride is not just carried out on a normal road, but additionally on a race track for some models.

September 18, 2009

SNELL & DOT basic requirement & its chance of failure.

To get Snell certification for a helmet, any manufacturer must sign a contract with the Snell foundation and pay for testing. The contract allows Snell to purchase up to 10% of their total helmet production at retail, test them to destruction, then be reimbursed for the retail cost of the helmets and the testing. The contract allows the helmet manufacturer to put Snell certification stickers in the helmet. If there is no numbered Snell sticker inside the helmet, it's not a Snell certified helmet. The sticker can make the helmet cost 50-100us$ more in store.

In the '80s, the US DOT got into the helmet certification business. Their standards were set in 1971, and the DOT has not substantially revised them since. Also, the DOT does not do consistent testing, so a DOT sticker does not carry the security that a Snell sticker carries. The DOT expects manufacturers to voluntarily test their own helmets and certify them themselves. If it happens that the DOT tests a helmet and the helmet fails, the DOT informs the manufacturer and expects them to voluntarily correct the problem.

In all of 2001, the DOT tested 40 helmets total, and 8 of them failed the test. Generally speaking, the DOT requirements tend to protect you at lower speeds, and the Snell requirements tend to protect you at higher speeds. Therefore, meeting both requirements is pretty tricky and results in a pretty good helmet.

However, absent the Snell sticker, you can't be certain the helmet even meets DOT requirements. In fact, some manufacturers make "beanie" helmets, popular with certain riders, and put DOT stickers on the helmets even though it's quite obvious that the helmet does not meet DOT standards at all. They do this because several court cases in several states have found that if you buy a helmet with a DOT sticker, then as a rider you're in compliance with the helmet law, even if the helmet does not actually meet DOT standards.

There has never been a fine levied against either a dealer or a manufacturer for misrepresenting a helmet as DOT compliant when it is not. Some people think the DOT standard actually offers slightly better protection than the Snell standard, and this may even be true. Unfortunately, due to the voluntary nature of DOT testing, you cannot be certain that a DOT helmet actually passes the DOT tests. The Federal Government should enforce the DOT regulation strictly as ECE and SNELL which are randamly tested in each production batch.


New Release of Masei Chrome Motorcycle Modular Helmet



They are new release of MASEI Chrome Modular Helmet. Retailing for US$130-195 now in store. For more details, please contact me!




September 10, 2009

SNELL stickers cost much more on Motorcycle Helmet


As mentioned, during the helmet absorption test, helmets are dropped, using gravity to accelerate the helmet to a given speed before it smashes onto a test anvil bolted to the floor. By varying the drop height and the weight of the magnesium headform inside the helmet, the energy level of the test can be easily varied and precisely repeated. As the helmet/headform falls it is guided by either a steel track or a pair of steel cables. That guiding system adds friction to slow the fall slightly, so the test technician corrects for this by raising the initial drop height accordingly.

The headform has an accelerometer inside that precisely records the force the headform receives, showing how many Gs the headform took as it stopped and for how long.

If you test a bunch of helmets under the same conditions, you can get a good idea of how well each one absorbs a particular hit. And it's important to understand that as in lap times, golf scores and marriages, a lower number is always better when we're talking about your head receiving extreme G forces.

The hardest Snell test for a motorcycle helmet is a two-strike test onto a hemispherical chunk of stainless steel about the size of an orange. The first hit is at an energy of 150 joules, which translates to dropping a 5-kilo weight about 10 feet—an extremely high-energy impact. The next hit, on the same spot, is set at 110 joules, or about an 8-foot drop. To pass, the helmet is not allowed to transmit more than 300 Gs to the headform in either hit.

Tough tests such as this have driven helmet development over the years. But do they have any practical application on the street, where a hit as hard as the hardest single Snell impact may only happen in 1 percent of actual accidents? And where an impact as severe as the two-drop hemi test happens just short of never?

The Snell sticker has become a marketing gimmick. A manufacturer puts that sticker in his helmet and he can increase the price by $50 to 100. Because the image associated with Snell means a better and stronger helmet. Therefore must be worth a whole lot more money.

September 6, 2009

SNELL / DOT Standard Comparison

There are two organizations setting safety standards for motorcycle helmets in the United States, the Federal Government's Department of Transportation (DOT) and the Snell Memorial Foundation. I would say DOT is the governmental and basic requirements for all helmets imported and used on roads, while SNELL is the standard measured by private non-profit organization, but not necessary on roads. SNELL is more for professional racers and is the world's toughest standard. However, it does not mean SNELL is better than DOT. For casual riders, DOT is better measurement and more protective to riders, because it is designed for normal riders with thicker liner part.

Both Snell and DOT position the helmet on a test headform and then drop that helmeted headform through a two guided falls onto a fixed steel anvil. The test is repeated so that each helmet is impacted on at least four different sites on its surface against either a flat or hemispherical shaped anvil. Snell testing also impacts the helmet against a steel edge anvil that may simulate the edge of a sign stanchion or guardrail. The differences are in impact severity and impact criteria. How big an impact must the helmet withstand and how do the testers determine that the helmet actually withstood the impact.

There are also administrative differences between Snell and DOT. Snell Certification means that Snell technicians in Snell labs tested samples of the helmet to Snell standards before the helmet was certified. Furthermore, as a condition of certification, Snell regularly buys samples of all Snell certified products and brings them into our lab for follow-up testing.

DOT certification is done on the honor system. The helmet's manufacturer determines whether his helmets satisfy DOT and then claims the qualification for himself. There is not even a reporting requirement. The government does contract for some spot check testing at commercial and private labs but not very much. In recent years much of their effort has been spent against so-called beanie helmets that are obviously substandard and are worn only by helmet law protesters.

About MASEI HELMET Tinted / Rainbow Visor & Local Dealership


During the last 2 weeks, I received many emails asking about Masei Helmet Tinted Visor and Windshield and local dealership. Please email your questions and requests to masei_helmet @ hotmail com directly. He is the sales representative.

September 5, 2009

DOT FMVSS218 - Novelty Helmet Not Safe?


According to the National Highway Traffic Safety Administration, motorcycle riders who do not wear helmets are 40 percent more likely to incur fatal head injuries than riders who do.

From 1984 through 1990, helmets saved the lives of more than 4,740 motorcyclists. To help protect the lives of motorcycle riders, the US Department of Transportation (DOT) requires that all motorcycle helmets sold in the United States meet Federal Motor Vehicle Safety Standard (FMVSS) 218.

Each year, DOT conducts compliance testing of a variety of motorcycle helmets to determine whether helmets being sold in the U.S. meet the federal safety standard. Because helmets add such a critical margin of safety for motorcycle riders, many states now have laws requiring the use of helmets that meet FMVSS 218 requirements.

Increasingly though, motorcycle riders are violating these state laws by wearing cheap and unsafe helmets that do not meet FMVSS 218. Most of these helmets are sold as novelty items by unscrupulous merchants to circumvent the FMVSS 218 requirements.

In some cases, people purchase these helmets in the mistaken belief that they offer protection. However, many people who wear these novelty helmets know that they are unsafe, but still wear them anyway. They are not enough to protect riders, because many DOT novelty helmets do not cover head enough or protect ear and side area well. Therefore, in other countries, all DOT helmets must cover ear parts.

September 4, 2009


In these years, this kind of helmet sunshield is gaining popularity in Asia. It is external sunshield which costs much less than internal sunshield. The pictured one is MASEI 828 type helmet. It comes to my attention that Hong Kong Policemen are currently using this kind of helmet

September 2, 2009

New Motorcycle Helmet Venting System; Air straight to your head

If you are wearing an open-face Helmet, you don't have to worry about venting and air flow. Full Face helmet requires a good venting system to keep your head cooling down from sweating, especially in summer time.

Motorcycle helmet air vents now come in all shapes and sizes, and the flow of air through a helmet is considered to be an important comfort factor. No standard for vent shapes exists and there doesn't seem to be any particular system that works better than others. The most common air flow methods used are variations on chin bar vents, top vents and exhaust vents in the back of the helmet.

We designed new Helmet Polystyrene Liners with 6-8 holes, directly letting the air flowing down or circulating around your hair and head area.

Helmet Impact Absorption Test for DOT & ECE

The ECE standard has the most stringent 'peak g' rating which on face value is the most re-assuring. However, while the other standards (SNELL and DOT) all employ a hemispherical anvil which increases the concentration of loading and challenges the shell to withstand puncturing, the ECE does not and the nearest equivalent is the kerbstone.

During the test, the helmet is fitted to a metal head (see picture) and dropped onto a steel anvil from a height of 287cm in order to get an impact speed of 27km/h. Four points on the helmet are each tested once and the anvils are both flat and rounded. Furthermore, the helmet is then dropped chinguard first onto a flat anvil from a height of 155cm. The velocity and duration of impact are both measured by sensors on the dummy head and when analysed, the acceleration of the head due to gravity must not exceed 275g.

The Head Injury Criteria (HIC) factor is a measurement of the total impact energy onto the head. It is usually calculated by multiplying the velocity with the duration of impact. The maximum permissible figure for this is 2,400. Reducing the total peak g and also the duration of impact will provide the rider with the best protection.

Chinstrap testing is also essential for helmets to get the necessary certificates.The chin strap is also tested by hanging a mass from it (a static load) and then dropping a proportion of this mass (a dynamic load) from a height of 75cm. This must not displace the chin strap by more than 35mm (from the dynamic load) and the static load must not displace the chin strap by more than 25mm.

video

If any question, please email me anytime.

September 1, 2009

New issue of MASEI Helmet (Featuring Tigers)


Quite a good looking motorcycle helmet!









Motorcycle Helmet Polystyrene Liner to absorb energy - DOT & ECE


The liner of the helmet is a very functional component and is designed to absorb and disperse an impact so it's not all directly transmitted to your skull. The shell will absorb a certain amount and this is the reason that it's not necessarily a bad thing to crack a helmet in a crash.


The liner is often made from expanded polystyrene, which is liked those white-colored packing material inside new TV or DVD sets in stores, acting against shocks too during the delivery. It works the same to the head too. However, different manufacturing techniques are used by different companies to get the greatest possible dispersion of impact forces. Helmets meeting the minimum federal safety standard (DOT) have 1-inch thick inner liner of appropriate firm polystyrene foam. Always, the inner liner is not visible. Unsafe helmets normally contain only soft foam padding or a bare plastic shell with no foam at all.

The density of this liner can not be too soft or too hard. DOT & ECE requires thicker liner than SNELL somehow. If you crash and hit your head the outer shell may look fine but the liner may have had to absorb the impact and by doing so the polystyrene may have been greatly compressed.


If there is a subsequent impact the liner will not be able to absorb or compress to the same degree and if the polystyrene is completely compressed it will offer no benefit and the forces will be transferred to the rider's head which may result in serious concussion.

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