Mar 30, 2026
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An Easy-to-Understand Explanation of Motorcycle Helmet Laws! Includes Examples of Violations
Legal Obligation to Wear a Motorcycle Helmet
Source: https://pixabay.com/ja/photos/A4-264220/
Helmets are crucial for protecting your head in the event of a fall, and there is a legal obligation to wear one when riding a motorcycle.
We will explain the laws and penalties related to the mandatory helmet use for motorcycles, as well as common misconceptions.
Road Traffic Act, Article 71-4
Article 71-4 of the Road Traffic Act is the basis for the mandatory helmet use when riding a motorcycle, and it stipulates the following:
"Drivers of large motorcycles or ordinary motorcycles must not operate a large motorcycle or an ordinary motorcycle without wearing a riding helmet, nor must they operate a large motorcycle or an ordinary motorcycle with a passenger who is not wearing a riding helmet.
2. Drivers of general motorized bicycles must not operate a general motorized bicycle without wearing a riding helmet."
Source: e-Gov
https://laws.e-gov.go.jp/law/335AC0000000105
It is stipulated that when driving large motorcycles and ordinary motorcycles, one cannot drive without wearing a riding helmet, and the second clause stipulates that even mopeds have a mandatory helmet-wearing requirement.
Thus, Article 71-4 of the Road Traffic Act is a provision that stipulates that helmet use is mandatory for all two-wheeled vehicles, whether mopeds or large motorcycles, when driving on public roads.
When riding a motorcycle on the road, this article serves as the basis for the mandatory helmet-wearing requirement, and riding without a helmet constitutes a violation of the law.
Applicable Vehicle Types
The vehicle types for which helmets are mandatory for two-wheeled vehicles are as follows:
| Vehicle Type | Helmet Obligation | Notes |
| Motorized bicycle (~50cc) | Mandatory | Class 1 Moped |
| Light motorcycle (51cc-125cc) | Mandatory | Class 2 Moped |
| Standard motorcycle (126cc-400cc) | Mandatory | Required for pillion riders as well |
| Large motorcycle (401cc~) | Mandatory | Safety is especially important due to highway use |
When riding a motorcycle on public roads, helmet use is mandatory for all motorcycles, whether they are 50cc mopeds or large motorcycles exceeding 400cc.
When riding two-up on a motorcycle that allows it, not only the driver but also the passenger in the rear seat is obligated to wear a helmet; failure to do so will result in a traffic violation.
Among them, for motorcycles with an engine displacement exceeding 125cc, which are capable of driving on expressways, higher speeds are possible, so wearing a full-face or jet helmet, which offers higher safety, is recommended.
Penalties for Violations
If you are caught by a police officer for not wearing a helmet while riding a motorcycle, you will be subject to the following penalties:
| Content | Response |
| Violation Name | Violation of mandatory riding helmet use |
| Penalty Points | 1 point added |
| Fine | None (administrative disposition only) |
| Notes | Subject to police questioning and enforcement (arrest). Accumulation of points may lead to license suspension or revocation. |
If you are caught by a police officer for not wearing a helmet while riding a motorcycle, you will be subject to the following penalties:
Common Misconceptions
Here are some "common misconceptions" regarding motorcycle helmet use:
- "Mopeds don't need helmets."
- "Just wearing a half-helmet is okay."
- "It's fine as long as you're wearing it, even if the chin strap isn't fastened."
- The driver is not responsible if a passenger doesn't wear a helmet.
Let's take a closer look at each of these misconceptions.
Misconception 1: Mopeds don't need helmets
There is a misconception that helmets are not required when riding a moped, but even for mopeds, wearing a helmet is mandatory, and not wearing one is a traffic violation.
Before 1986 (Showa 61), helmet use was not mandatory for mopeds, but due to frequent fatal accidents involving mopeds, the mandatory helmet use was extended to include mopeds.
Helmet use is now mandatory for all motorcycles, regardless of engine displacement, including mopeds.
Misconception 2: Just wearing a half-helmet is okay
Wearing a half-helmet when riding a motorcycle is not a violation, but in the event of a fall, it may not adequately protect the head or face, potentially leading to serious injury.
When riding with a half-helmet on an expressway or on a windy day, the helmet is prone to shifting or coming off your head due to wind pressure, thus failing to perform its function as a helmet.
Motorcycle helmets are worn to protect the head and face, which are prone to fatal injuries in the event of a fall, so prioritizing fashion over safety is counterproductive from a safety standpoint.
Misconception 3: It's fine as long as you're wearing it, even if the chin strap isn't fastened
While wearing a motorcycle helmet is mandatory, fastening the chin strap is not explicitly stipulated, so not fastening it is not a violation.
However, motorcycle helmets play a role in protecting the head and face in situations like falls, and if the chin strap is not fastened, the helmet may come off during a fall, potentially leading to a severe head injury.
To protect your head in the event of an emergency such as a fall, fastening the chin strap is essential, so not only wear your helmet but also fasten the chin strap securely.
Misconception 4: The driver is not responsible if a passenger doesn't wear a helmet
Motorcycles that can carry two people (motorcycles with an engine displacement of 51cc or more) can carry a passenger in the rear seat (tandem riding), but not only the driver but also the passenger is obligated to wear a helmet.
When riding a motorcycle, all occupants are obligated to wear a helmet, and if a passenger is caught by the police without wearing a helmet, the driver will be penalized (1 point added for violation, no fine).
Furthermore, if a passenger is injured, the driver will also be held responsible, so when riding with a passenger, ensure they wear safe clothing and equipment as much as possible.
Legally Recognized Standards for Motorcycle Helmets
Source: https://pixabay.com/ja/photos/BC-6288958/
There are various types of helmets, but not just any helmet is acceptable. As shown in the table below, you must choose a helmet that is suitable for motorcycle riding.
| No. | Standard Content | Explanation |
| 1 | Structure that does not obstruct left, right, or upward vision | If peripheral vision cannot be ensured, safe driving becomes difficult. Jet and full-face types generally clear this. |
| 2 | Structure where the visor does not droop due to wind pressure, obstructing vision | If the visor is too soft, it may drop down during riding, which is dangerous. |
| 3 | Structure that does not significantly impair hearing | Sufficient ventilation and hearing are required to hear approaching vehicles and horns. |
| 4 | Possesses impact absorption and the shell has penetration resistance | Structure that can protect the head in the event of a fall or impact. Many use expanded polystyrene material. |
| 5 | Structure that prevents easy detachment upon impact and can be secured with a chin strap | If the chin strap is not fastened, the helmet is prone to coming off, potentially leading to a violation. |
| 6 | Weight of 2kg or less | Too heavy can strain the neck, which is disadvantageous for safety. Usually, most are 1.5kg or less. |
| 7 | Structure that does not pose a risk of injuring the human body | Spikes, sharp decorations, or metallic protrusions are not allowed. The reason is that they can exacerbate injuries in an accident. |
Reference: e-gov Law Search
https://laws.e-gov.go.jp/law/335M50000002060
When wearing a helmet, it is necessary to choose one with a structure that ensures left, right, and upward vision, and prevents the visor from drooping due to wind pressure and obstructing vision.
Furthermore, the structure must not significantly impair hearing. If vision is not ensured, safe driving is not possible, and if hearing is impaired, it becomes difficult to notice other vehicles and motorcycles, which is dangerous.
In addition, it must have impact absorption and a structure that protects the head in the event of a fall. A structure that can be securely fastened with a chin strap and prevents detachment during a fall is also not allowed.
If a helmet does not meet the conditions in the table above, it cannot clear the safety standards for motorcycle helmets, so riding a motorcycle while wearing a construction helmet, for example, is not allowed.
Road Traffic Act Enforcement Regulations Article 9-5
Article 9-5 of the Road Traffic Act Enforcement Regulations stipulates the standards for helmets.
Additionally, based on the safety standards obtained by helmet manufacturers, there are marks as shown below. When choosing a helmet, select one with these marks.
- PSC Mark
- SG Mark
- JIS Standard
Let's explain in detail what each mark represents.
PSC Mark
The PSC mark is attached to products that meet national safety standards, and it is called the PSC mark from the initials of Product, Safety, and Consumer.
It applies to specific products designated by the Ministry of Economy, Trade and Industry (such as riding helmets, household pressure cookers), and its purpose is to prevent accidents caused by products and ensure safety in daily life.
Target items include "specified products" for which manufacturers and importers are obligated to conduct self-confirmation, and "special specified products" for which inspection by a third-party organization is mandatory under stricter standards. Products without a PSC mark cannot be sold.
SG Mark
The SG mark, an abbreviation for "Safe Goods," is affixed to products that comply with the safety standards established by the "Product Safety Association of Japan."
It applies to products that may affect the lives and bodies of consumers, and it sets safe standards (SG standards) for product structure, materials, and usage.
The target products range from infant products to sports equipment, and if a consumer is injured due to a product bearing the SG mark, the Product Safety Association will pay up to 100 million yen in damages.
JIS Standard
The JIS standard sets rules regarding the safety and quality of products and services, ensuring that the quality of Japanese products is maintained at a certain level or higher.
Abbreviated as JIS (Japanese Industrial Standards), it is a national standard based on the Industrial Standardization Act (JIS Act).
The purpose is to maintain a certain level or higher of product and service quality at the national level. For example, it defines the diameter of household electrical outlets, dimensions of cross-recessed screws, paper sizes (A4, B3, etc.), and their quality, performance, and functions.
Examples of Helmets That May Be Illegal
Just wearing any helmet on your head is not sufficient, and certain uses, as described below, may be illegal.
- No helmet
- Chin strap not fastened
- Fashion helmets
- Half-helmets
Let's take a closer look at each of the usage methods that may be illegal.
No helmet
"No helmet" refers to a state where no helmet is worn at all. As of 2025, all motorcycles, from mopeds to large motorcycles, cannot be operated without wearing a helmet.
Not only the driver, but also passengers in the rear seat of two-seater motorcycles are required to wear helmets. If caught driving without a helmet, a police officer will issue a violation.
Some newspaper delivery personnel drive without helmets in the early morning, but this is a traffic violation, as driving without a helmet is not permitted simply because one is a newspaper delivery person.
A helmet is for protecting yourself in the event of a fall and should not be worn for fashion or convenience (it's troublesome to wear, it gets stuffy).
Chin strap not fastened
Even if the chin strap is not fastened, you will not be issued a violation notice during enforcement, but a police officer may advise you to "fasten your chin strap."
Furthermore, if the chin strap is not fastened, there is a high possibility that the helmet will come off due to impact during a fall, etc., and will not be able to protect the head.
Helmets are worn as a safety feature to protect the head, so fasten the chin strap securely to prevent the helmet from coming off while riding a motorcycle.
Fashion helmets
Fashion helmets, which prioritize decoration and design over safety, are also helmets that should be avoided for motorcycle riding.
Fashion helmets do not need to meet the standards required for motorcycle helmets in terms of safety, so they have problems with safety and performance.
Not just any helmet shaped like one is acceptable. You should wear a helmet that meets the safety performance and functionality required for motorcycles.
Half-helmets
Motorcycle half-helmets are not illegal, but they are highly unlikely to protect the head and face in the event of a fall compared to full-face helmets, so it's best to avoid choosing them.
Since they are only secured at two points (head and chin strap), they are prone to shifting due to wind pressure while riding, and because they do not cover the back of the head or face, injuries are more likely in the event of a fall.
Safety should be the top priority for helmets, so full-face, jet, or modular helmets, which offer higher safety, are recommended.
Recommended Helmets That Meet Legally Recognized Conditions
We will introduce six motorcycle helmets that meet legal standards.
If you're unsure which motorcycle helmet to choose, use the items introduced here as a reference.
DN-001RS Full-Face Helmet White DAYTONA
Source: https://bikeman.jp/products/d-vr-t-000820
The DAYTONA "DN-001RS Full-Face Helmet" is a cost-effective motorcycle helmet with an inner visor.
Made from a composite material of ABS and PC, and priced under 20,000 yen, it clears the SG and PSC standards required for motorcycle helmets.
- Type: Full-face
- Product Name: DN-001RS Full-Face Helmet White
- Manufacturer: DAYTONA
- Applicable Standards: SG, PSC
- Sales Price (tax included): 18,616 yen
N808 WANTED NOLAN
Source: https://bikeman.jp/products/d-45666
"N808 WANTED" is a helmet from NOLAN, a brand with over 50 years of history in Italy. Its European design, different from Japanese helmets, is suitable for both city riding and touring.
DAYTONA, the exclusive importer of NOLAN products in Japan and a motorcycle parts manufacturer and distributor, produces them to comply with Japanese SG standards, ensuring safety and legal compliance.
- Type: Full-face
- Product Name: N808 WANTED
- Manufacturer: NOLAN
- Importer and Distributor: DAYTONA
- Applicable Standards: SG, PSC
- Sales Price (tax included): 39,547 yen
N80-8 Solid Metal White NOLAN
Source: https://bikeman.jp/products/d-28987
The NOLAN "N80-8 Solid Metal White" is a full-face helmet equipped with an inner visor that functions as sunglasses and can be stored with a single push of a button.
LPC (Liner Position Control) allows for height adjustment of the interior, and the cheek pads can be removed simply by pulling a red tape, offering high functionality that facilitates removal in case of emergency.
- Type: Full-face
- Product Name: N80-8 Solid Metal White
- Manufacturer: NOLAN
- Importer and Distributor: DAYTONA
- Applicable Standards: SG, PSC
- Sales Price (tax included): 32,355 yen
X-804RS Ultra Carbon SPECTRE Blue
Source: https://bikeman.jp/products/d-45230
The NOLAN "X-804RS Ultra Carbon SPECTRE" is recommended for those who engage in sport riding, such as circuit driving.
It uses high-end materials such as carbon and aramid fiber, also found in professional racing helmets, offering high strength, safety, lightness, and comfort. It is a flagship model with aerodynamic performance designed for racers.
- Type: Full-face
- Product Name: X-804RS Ultra Carbon SPECTRE Blue
- Manufacturer: NOLAN
- Importer and Distributor: DAYTONA
- Applicable Standards: SG, PSC
- Sales Price (tax included): 101,563 yen
HJH190 i90 Hollen System Helmet RS Taichi
Source: https://bikeman.jp/products/rst-hjh190ye01l
The RS Taichi "HJH190 i90 Hollen System Helmet" is a system helmet rich in functionality, such as a retractable sun visor and a rapid-fire shield removal system.
It also features space for intercom-related equipment like speakers and microphones, and is equipped with a ventilation system that efficiently draws in riding wind and expels internal heat.
- Type: System
- Product name: HJH190 i90 Hollen System Helmet
- Manufacturer: RS Taichi
- Compatible standards: SG, JIS
- Selling price (tax included): 29,920 yen
KAMUI 3 JAG Black Blue
Source: https://bikeman.jp/products/ogk-4966094596699
The OGK Kabuto "KAMUI 3 JAG Black Blue" features a tribal pattern and sharp design, offering ease of putting on and taking off, and a comfortable fit that softly wraps around the neck.
It uses Teijin's high-performance polycarbonate to cut both UV (ultraviolet) and IR (infrared) rays, and the cheek pads are designed to easily accommodate glasses or sunglasses.
- Type: System
- Product name: KAMUI 3 JAG Black Blue
- Manufacturer: OGK Kabuto
- Compatible standards: JIS
- Selling price (tax included): 38,649 yen
Penalties for Violations
If you ride a motorcycle on public roads without wearing a helmet, you may be subject to the following penalties:
| Item | Content |
| Violation Name | Failure to wear a helmet while riding |
| Legal Basis | Road Traffic Act Article 71-4, Road Traffic Act Enforcement Order Article 26-3 |
| Applicable to | Drivers and passengers (all motorcycles, including mopeds) |
| Penalty Points | 1 point added (administrative disposition) |
| Fine | None (no monetary penalty imposed) |
| Criminal Penalty | None (processed as a traffic violation) |
If you ride a motorcycle without wearing a helmet, it constitutes a violation of the helmet-wearing obligation while riding (Road Traffic Act Articles 71-4 and 26-3), resulting in 1 penalty point and no fine.
Legal Risks of Using Half-Cap Helmets
Source: https://pixabay.com/ja/photos/88-3097712/
Half-cap helmets are legally ambiguous and may be considered a violation, so it's safer to avoid using them.
Even if you are not caught by the police, the significantly lower safety of half-caps compared to full-face helmets is another reason to avoid them.
Half-cap helmets are highly likely to come off easily during an impact, such as a fall, failing to perform their role of protecting the head. The legal ambiguity and unreliability in terms of safety are the risks associated with using half-cap helmets.
Reasons Why It May Be a Violation
Even if it's a motorcycle helmet, it may constitute a traffic violation for the following reasons:
- Insufficient impact absorption and penetration resistance in many products
- Many products do not comply with safety standard marks (PSC, SG, JIS)
- Incomplete protection of the entire head
When choosing a motorcycle helmet, make sure there is no possibility of these violations.
Insufficient impact absorption and penetration resistance in many products
The Road Traffic Act stipulates that helmets must "have impact absorption and the shell must have penetration resistance" as a standard. Helmets that do not meet these conditions are considered violations.
Many inexpensive helmets do not meet the impact absorption and shell penetration resistance requirements, which could lead to being stopped by the police.
Furthermore, impact absorption and penetration resistance are essential conditions for protecting the head. For safety reasons, avoid choosing inexpensive helmets (around 10,000 yen) that do not meet these requirements.
Many products do not comply with safety standard marks (PSC, SG, JIS)
There are various types and sellers of motorcycle helmets, but many inexpensive helmets do not clear safety standard marks (PSC, SG, JIS) and may be considered a violation.
Especially helmets priced under 10,000 yen often do not meet safety standards, so choosing a helmet based solely on price is dangerous from a safety perspective.
While it's tempting to choose a cheaper helmet due to budget constraints, a helmet is meant to protect your safety, so prioritize safety over price as much as possible.
Wearing a helmet that is inferior in safety increases the likelihood of permanent injury due to head damage, resulting in greater harm than the money saved on the helmet. Therefore, it is recommended to choose a helmet that meets safety standards.
Incomplete protection of the entire head
Motorcycle helmets are intended to protect the head, so if the entire head is not protected, you may be subject to police enforcement.
Legally (Road Traffic Act Enforcement Regulations Article 9-5, Standards for Riding Helmets), a half-cap helmet is not a violation, but a helmet that prioritizes design too much may not be recognized as a motorcycle helmet.
Since safety is inferior and there is a possibility of violation, it is recommended to choose a motorcycle helmet that firmly covers the entire head.
History of Motorcycle Helmet Laws
Source: https://pixabay.com/ja/photos/BC-5040167/
Before 1965, the wearing of riding helmets was not specifically mandated, but the obligation to wear helmets was strengthened in stages as follows:
| Year | Content | Remarks |
| 1965 (Showa 40) | Helmet use for motorcycles on expressways established as a "duty to endeavor" | No legal penalties. Initial response to increased fatalities. |
| 1972 (Showa 47) | Mandated helmet use for motorcycles 51cc and above in designated sections (expressways, arterial roads, etc.) | At this point, only large and medium-sized motorcycles were covered. Mopeds were excluded. |
| 1975 (Showa 50) | Expanded to all designated sections by government ordinance, making helmet use "always mandatory" for motorcycles 51cc and above | Application spread not only to arterial roads but also to general roads. |
| 1978 (Showa 53) | "Completely mandated" helmet use for motorcycles 51cc and above on all roads | High fatality rate from motorcycle accidents was the background. |
| 1986 (Showa 61) | Mandatory use expanded to mopeds (50cc and below), making it completely mandatory for all motorcycles | Fatalities involving mopeds had also become serious, leading to full enforcement. |
| Present (2020s) | Completely mandated for all displacements, all roads, drivers & passengers | Not wearing a helmet is a Road Traffic Act violation (1 penalty point added), passengers also subject. |
First, in 1965, helmet use was mandated for motorcycles on expressways, expanding in 1972 to designated sections (expressways and some arterial roads).
Three years later, in 1975, helmet use became mandatory on all government-designated roads (except for mopeds), and in 1986, helmet use was also introduced for mopeds.
In the 2020s, helmet use became mandatory for all motorcyclists, regardless of engine displacement, on all roads, covering both drivers and passengers, which remains the case today.
Why was it mandated in stages?
The gradual mandating of motorcycle helmets was due to an increase in accidents, especially fatal ones.
Initially, the obligation was limited to expressways and arterial roads where speeds are higher and damage from falls is more severe, but as fatalities also increased on general roads, the types of motorcycles covered by the mandate expanded in stages.
The history of helmet wearing obligation is marked by a gradual expansion of its scope as fatal and other serious accidents increased.
Effectiveness of the Mandate
A survey by the Institute for Traffic Accident Research and Data Analysis (ITARD) revealed that riders who did not wear helmets sustained more than twice as many head injuries compared to those who wore them correctly.
Out of 280 motorcycle accidents surveyed by the center, 67.4% of riders involved in accidents without helmets sustained head injuries.
Conversely, head injuries among riders who wore helmets correctly remained at 30.8%, meaning head injuries were less than half, demonstrating the high effectiveness of helmet use.
Reference: Institute for Traffic Accident Research and Data Analysis (ITARD)
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