Rules for Passing Bicycles by Car, and Bicycles on the Shimanami Kaido

From April 1, 2026, a Rule for Passing on the Right Side of a Bicycle Applies

Paragraphs 3 and 4 were added to Article 18 of the Road Traffic Act. In the history of the law on e-Gov Law Search, the version of June 1, 2025, just before, has only paragraphs 1 and 2 in Article 18, and paragraphs 3 and 4 appear from the version of April 1, 2026. This is one of the enforcement dates of Act No. 34 of Reiwa 6, promulgated on May 24, 2024. The cover of the Ehime Prefectural Police pamphlet also says “令和８年４月１日施行” (in force April 1, Reiwa 8 (2026)).

Today (October 13, 2026) is more than 6 months after the start. Another amending act (Act No. 52 of Reiwa 8) also came into force on July 21, 2026, but the text of Article 18 is the same as in the April 1 version.

Paragraph 3 is the rule for when a car or similar passes on the right side of a bicycle going the same direction.

車両（特定小型原動機付自転車等を除く。）は、当該車両と同一の方向に進行している特定小型原動機付自転車等（歩道又は自転車道を通行しているものを除く。）の右側を通過する場合（当該特定小型原動機付自転車等を追い越す場合を除く。）において、当該車両と当該特定小型原動機付自転車等との間に十分な間隔がないときは、当該特定小型原動機付自転車等との間隔に応じた安全な速度で進行しなければならない。

Translation: “When a vehicle (excluding specified small motorized bicycles and the like) passes on the right side of a specified small motorized bicycle or the like (excluding one on a sidewalk or a bicycle path) that is going in the same direction as the vehicle (excluding the case of overtaking that specified small motorized bicycle or the like), and there is not a sufficient gap between the vehicle and that specified small motorized bicycle or the like, the vehicle must proceed at a safe speed suited to the gap from that specified small motorized bicycle or the like.”

Paragraph 4 is the rule for the bicycle side.

前項に規定する場合においては、当該特定小型原動機付自転車等は、できる限り道路の左側端に寄つて通行しなければならない。

Translation: “In the case set out in the preceding paragraph, that specified small motorized bicycle or the like must drive as far to the left edge of the road as possible.”

“Specified small motorized bicycles and the like” (特定小型原動機付自転車等) are defined in Article 18, paragraph 1 as “specified small motorized bicycles and light vehicles.” Bicycles are included in the light vehicles of Article 2, paragraph 1, item 11 (a). The National Police Agency material also describes the side that is passed on the right like this.

(*2)軽車両（自転車を含む）及び特定小型原動機付自転車

Translation: “(*2) Light vehicles (including bicycles) and specified small motorized bicycles”

Specified small motorized bicycles are described on the JB Honshi Expressway page as “so-called electric kickboards and the like.” The “cars and the like” on the passing side are written in the same material as “motor vehicles, general motorized bicycles and trolley buses.”

There are 3 conditions that can be read from the statute.

Passing on the right side of a bicycle going in the same direction
Overtaking is not included in this paragraph
Bicycles on sidewalks or bicycle paths are not covered

There Is No Figure for “a Sufficient Gap,” and There Are 2 Guides

Article 18, paragraph 3 gives neither meters nor speed. The figures come from a National Police Agency “guide” and an Ehime Prefecture appeal.

The National Police Agency overview material shows a guide for how to pass.

自動車等が自転車等の右側を通過するときは、できる限り間隔を空けましょう。少なくとも１メートル程度間隔を空けることが安全です。

Translation: “When a car or the like passes on the right side of a bicycle or the like, leave as much gap as possible. It is safe to leave a gap of at least about 1 meter.”

自転車等と１メートル程度の間隔を確保できない場合には、時速20キロメートルから30キロメートル程度で運転しましょう！

Translation: “If you cannot secure a gap of about 1 meter from the bicycle or the like, drive at about 20 to 30 kilometers per hour!”

The same material also has a note about the figures.

※ 上記はあくまで目安です。自動車等が自転車等の右側を通過する際の「十分な間隔」や「間隔に応じた安全な速度」については、自動車等と自転車等との具体的な走行状況、道路状況や交通状況等により異なります。

Translation: “※ The above is only a guide. The ‘sufficient gap’ and the ‘safe speed suited to the gap’ when a car or the like passes on the right side of a bicycle or the like differ depending on the specific driving situation of the car and the bicycle, road conditions, traffic conditions and so on.”

Separately from this, Ehime has the “Omoiyari 1.5 m Campaign” (思いやり1.5m運動). The Ehime Bicycle Safe Use Research Council (愛媛県自転車安全利用研究協議会) began it on November 15, 2015, and the prefecture’s page says this.

自動車等の運転者に対し、自転車の側方を通過するときは“1.5メートル以上の安全な間隔を保つ”か、道路事情等から安全な間隔を保つことができないときは“徐行する”ことを呼び掛ける運動です。

Translation: “This is a campaign that calls on drivers of cars and the like to ‘keep a safe gap of 1.5 meters or more’ when passing beside a bicycle, or to ‘slow down’ when a safe gap cannot be kept because of road conditions and the like.”

Source	What it says	Status
Road Traffic Act, Article 18, paragraph 3	When there is not “a sufficient gap,” proceed at “a safe speed suited to the gap”	Law (no figure)
National Police Agency overview material	At least about 1 meter. If not possible, about 20 to 30 km/h	Guide
Ehime’s Omoiyari 1.5 m Campaign	1.5 meters or more. If not possible, slow down	Appeal

The prefectural council’s Q&A also explains that 1.5 meters is not a figure in the ordinance. It also includes a calculation that one lane of a standard road is about 3.5 meters wide, and that keeping 1.5 meters needs at least about 3.9 meters. This Q&A is from July 2016 and was written before Article 18, paragraph 3 came in.

Overtaking Is Article 28. Just Passing Beside Is Article 18, Paragraph 3

The parenthesis in Article 18, paragraph 3 leaves out overtaking. “Overtaking” (追越し) is defined in Article 2, paragraph 1, item 21 like this.

車両が他の車両等に追い付いた場合において、その進路を変えてその追い付いた車両等の側方を通過し、かつ、当該車両等の前方に出ることをいう。

Translation: “When a vehicle catches up with another vehicle or the like, it means changing its course, passing beside the vehicle or the like it has caught up with, and getting in front of that vehicle or the like.”

Article 28 applies to overtaking in which you get in front of a bicycle. Paragraph 1 requires passing on the right side of the vehicle ahead, and paragraph 4 says this.

前三項の場合においては、追越しをしようとする車両（次条において「後車」という。）は、反対の方向又は後方からの交通及び前車又は路面電車の前方の交通にも十分に注意し、かつ、前車又は路面電車の速度及び進路並びに道路の状況に応じて、できる限り安全な速度と方法で進行しなければならない。

Translation: “In the cases of the preceding 3 paragraphs, a vehicle about to overtake (called the ‘rear vehicle’ in the next Article) must pay full attention to traffic from the opposite direction or from behind and traffic ahead of the vehicle ahead or the tram, and must proceed at the safest speed and in the safest way possible according to the speed and course of the vehicle ahead or the tram and the condition of the road.”

The prefectural council’s Q&A explains 3 points about the movement when overtaking.

Overtaking a bicycle involves a change of course, so a signal (turn signal) is needed
On roads with an orange solid center line where crossing it is prohibited, or when an oncoming car is near, keep as much gap as possible and slow down
If you cannot overtake safely even by slowing down, stop overtaking until you can do so safely

Slowing down (徐行) is defined in Article 2, paragraph 1, item 20 as “proceeding at a speed at which a vehicle or the like can stop immediately.” The Q&A says that the council interprets slowing down when passing beside a bicycle as “the minimum speed needed to pass the bicycle safely.”

What Happens If the Rule Is Not Followed

Article 18, paragraphs 3 and 4 each have their own penalty provision.

Side	Article	Penalty	Blue ticket and similar treatment (Ehime Prefectural Police pamphlet)
Cars and others passing	Article 119, paragraph 1, item 6	Imprisonment of up to 3 months or a fine of up to 50,000 yen	2 violation points. Fines: regular car 7,000 yen, large vehicle 9,000 yen, motorcycle 6,000 yen, motorized bicycle etc. 5,000 yen
Bicycles and others	Article 120, paragraph 1, item 2	A fine of up to 50,000 yen	Fine 5,000 yen (violation of the duty of the vehicle being passed at the side)

The start of Article 119 is “A person who falls under any of the following items shall be punished by imprisonment of up to 3 months or a fine of up to 50,000 yen,” and the start of Article 120 is “A person who falls under any of the following items shall be punished by a fine of up to 50,000 yen.”

There are other provisions. Article 117-2-2, paragraph 1, item 8 sets imprisonment of up to 3 years or a fine of up to 500,000 yen for a person who, with the aim of obstructing the passage of other vehicles, acts in a way that would be a violation of Article 18, paragraph 3, in a manner that may cause danger to traffic on the road.

Further, Article 117-2, paragraph 1, item 4 sets imprisonment of up to 5 years or a fine of up to 1,000,000 yen for a person who commits this offense and thereby causes serious danger to traffic on the road, such as stopping another car on an expressway or similar road.

Ehime Prefecture’s Ordinance Says Drivers Must “Endeavor”

Ehime has the “Ordinance on Promoting Safe Use of Bicycles in Ehime Prefecture” (愛媛県自転車の安全な利用の促進に関する条例), in force from July 1, 2013. According to the prefecture’s page, the basic idea is “Share the Road,” in which pedestrians, bicycles, cars and others share the road with consideration. Article 6 says this about drivers of cars and motorized bicycles.

自動車等の運転者は、自転車が車両であることを認識し、歩行者、自転車及び自動車等が共に道路を安全に通行することができるように配慮するよう努めなければならない。

Translation: “Drivers of cars and the like must endeavor to recognize that bicycles are vehicles and to give consideration so that pedestrians, bicycles and cars and the like can all use the road safely.”

自動車等の運転者は、自転車の側方を通過するときは、これとの間に安全な間隔を保ち、又は徐行するよう努めなければならない。

Translation: “When passing beside a bicycle, drivers of cars and the like must endeavor to keep a safe gap from it or to slow down.”

The prefecture’s page says “なお、本条例における罰則の規定はありません。” (Please note that this ordinance has no penalty provisions.) The ordinance’s “must endeavor” and the Road Traffic Act’s Article 18, paragraph 3, “must proceed,” are different rules.

Where Bicycles Ride on the Shimanami Kaido

The Shimanami Kaido (Nishiseto Expressway) is described on the JB Honshi Expressway page like this.

尾道と今治を結ぶ西瀬戸自動車道(愛称「瀬戸内しまなみ海道」)は全長約60kmの自動車専用道路です。橋梁区間には歩行者、自転車、および125cc以下の原付専用の通路が設けられています。

Translation: “The Nishiseto Expressway (nickname ‘Setouchi Shimanami Kaido’), which connects Onomichi and Imabari, is a motor-vehicle-only road about 60 km long. On the bridge sections, paths exclusively for pedestrians, bicycles and mopeds of 125 cc or less are provided.”

The bicycle paths are provided separately from the expressway roadway. Their location on each bridge, from the JB Honshi Expressway page, is as follows.

Bridge	Where the bicycle-pedestrian path is
Kurushima-Kaikyo Bridge (来島海峡大橋)	Installed along the inbound (Onomichi direction) expressway. The moped path is on the outbound (Imabari direction) side
Omishima Bridge (大三島橋), Hakata-Oshima Bridge (伯方・大島大橋)	The moped path and the bicycle-pedestrian path are installed along the inbound (Onomichi direction) expressway
Ikuchi Bridge (生口橋), Tatara Bridge (多々羅大橋)	The bicycle-pedestrian path is on the outbound (Imabari direction) side, and the moped path is along the inbound (Onomichi direction) expressway
Innoshima Bridge (因島大橋)	The moped and bicycle-pedestrian path is inside the bridge girder

The entrance to the bridge paths is separate from the entrance for cars.

原付道・自転車歩行者道への入口は、高速道路のインターチェンジとは異なります。誤って高速道路に入らないようご注意ください。

Translation: “The entrances to the moped path and the bicycle-pedestrian path are different from the interchanges of the expressway. Please be careful not to enter the expressway by mistake.”

The JB Honshi Expressway page “How to use the bicycle-pedestrian path” also says that the entrances and exits from ordinary roads to the bicycle-pedestrian path on a bridge are at places separate from the ICs of the motor-vehicle-only road. The same page on the “moped path and bicycle-pedestrian path” says that mopeds, bicycles and pedestrians cannot enter from Mukaishima IC.

Specified small motorized bicycles such as electric kickboards use the bicycle-pedestrian path on the bridges. The JB Honshi Expressway page says “自転車歩行者道をご利用ください。(原付道は通行できません。)” (Please use the bicycle-pedestrian path. The moped path cannot be used.). The “bicycles and the like” in Article 18, paragraph 3 also include these vehicles.

Where You Meet Bicycles on Ordinary Roads Between Bridges

On the JB Honshi Expressway pages, the bicycle path on a bridge is a path separate from the expressway roadway, and its entrance is in a different place from the car entrance. For ordinary roads between bridges, it says this.

橋梁区間以外では、一般道にサイクリングのルートを示すブルーラインが引かれています。尾道や今治など目的地までの距離もライン上に明示されているので、ラインに沿って走れば安心！

Translation: “Outside the bridge sections, a blue line showing the cycling route is drawn on the ordinary roads. The distance to destinations such as Onomichi and Imabari is also shown on the line, so you can ride along the line with confidence!”

The page of the Ehime-side council (Shimanami Kaido Bicycle Road Promotion Council, Ehime Office (しまなみ海道自転車道利用促進協議会　愛媛事業本部)) has an explanation that refers to the same thing.

ルートには、ブルーラインや進行方向と残りの距離数を記載した路面標示が設置され、サイクリストが地図を持たなくても目的地に到着できるようにしています。

Translation: “On the route, a blue line and road markings showing the direction of travel and the remaining distance are installed, so that cyclists can reach their destination without carrying a map.”

On Ehime Prefecture’s “Notteru! Ehime” (ノッてる！えひめ) site, these road markings are called “Anshin Navi” (安心ナビ), and it explains with photos that they are drawn on the left side of the roadway.

Where the blue line is on the roadway is written on a Hiroshima Prefecture page. It is an explanation posted in August 2014 about work on roads managed by Hiroshima Prefecture (the Hiroshima side).

ブルーのラインは，車道左端に幅２０ｃｍで設置しております。

Translation: “The blue line is installed at the left edge of the roadway, 20 cm wide.”

One purpose of the installation is an appeal to drivers.

自動車運転者に対して，自転車への注意を喚起する。

Translation: “To call drivers’ attention to bicycles.”

The width of the blue line on the Ehime side and the road managers who installed it could not be confirmed in the materials this time.

Guidance from public organizations’ pages that relates to catching up with a bicycle on an ordinary road is as follows.

About riding side by side. JB Honshi Expressway guides cyclists to ride in a single line both on ordinary roads and on the bridges. It writes that riding abreast is dangerous, giving as reasons that roads are narrow and that other vehicles and pedestrians are there.
About night. The same page says “島や海は夜になると真っ暗です。” (The islands and the sea become pitch dark at night.) and calls on cyclists to check that their bicycle lights work.
About wind. The JB Honshi Expressway bridge page says “海峡部は風が強いことがありますのでご注意ください。” (Please be careful, as the wind can be strong over the straits.) This is an explanation about the bridge paths.
About bicycles on sidewalks. The Ehime Prefectural Police says “自転車は、歩車道の区別のある道路では、車道を通行しなければなりません。” (On roads with a distinction between sidewalk and roadway, bicycles must use the roadway.) and then shows when ordinary bicycles may use a sidewalk. Article 18, paragraph 3 leaves out bicycles on sidewalks.
About bicycle movement. The prefectural council’s Q&A asks drivers, in situations where they cannot cross the center line, to pass by “slowing down while paying full attention to sudden movements of the bicycle” (July 2016).

The page of the prefecture’s Omoiyari 1.5 m Campaign gives as background to the campaign that accidents in which cars and the like hit bicycles from behind are not uncommon, and that once one occurs, the rate of death of the bicycle rider tends to be extremely high.

3 Points to Keep in Mind Before You Drive

When passing on the right side of a bicycle going the same direction, if there is not “a sufficient gap,” proceed at “a safe speed suited to the gap.” It has been in force since April 1, 2026.
The guide for the gap is about 1 meter for the National Police Agency and 1.5 meters or more for Ehime’s campaign. If it cannot be kept, the former says about 20 to 30 km/h, and the latter says slow down.
On the bridges of the Shimanami Kaido, bicycles ride on a separate path. The place where you meet them on the same roadway is the ordinary roads between the bridges.

About This Article

What is written here was checked on October 13, 2026, on the pages of e-Gov Law Search, the National Police Agency, the Ehime Prefectural Police, Ehime Prefecture, JB Honshi Expressway and Hiroshima Prefecture. It was not checked by driving.

There are 3 things that could not be checked. The original text of the supplementary provisions of Act No. 34 of Reiwa 6 (the provision on the enforcement date) could not be obtained, and the enforcement date was checked against the history of the law and the Ehime Prefectural Police pamphlet. The prefectural council’s Q&A is from July 2016, and it is not known whether it was revised after Article 18, paragraph 3 came into force. The width and installer of the blue line on the Ehime side are also not in the materials this time.

Statutes and fine amounts may be revised. Before you leave, please check the current content on the pages of the National Police Agency and the Ehime Prefectural Police.