Japan Ordinary Motorcycle Theory key terms

A motorcycle with an engine displacement over 50 cc and up to 400 cc, ridden under a 普通自動二輪 licence; 小型自動二輪 (up to 125 cc) is a subcategory with its own licence type.

A motorized two-wheeler with engine displacement of 50 cc or less (or rated output up to 0.6 kW for electrics), requiring a 原付 licence and subject to 30 km/h speed limits and two-stage right turns.

A right-turn method used by 原付 and some other vehicles at multi-lane intersections: instead of crossing traffic, the rider proceeds straight to the far corner, turns to face the new direction, and waits for the light.

Turning right at an intersection; motorcycles other than 原付 generally turn right from the right edge of the lane, keeping close to the centre line while watching oncoming traffic.

Changing lane or lateral position on the road; the rider must signal with the indicator, check mirrors and blind spots, and confirm safety before moving, completing the change smoothly.

Checking that a turning large vehicle is not about to cut across your path; riders should never enter the inside of a truck or bus that has signalled a turn.

The difference in turning radius between a vehicle's front inner wheel and rear inner wheel; large vehicles swing their rear body inward, so standing beside a turning truck is dangerous.

Areas around a vehicle that the driver cannot see directly or in mirrors; riders should avoid lingering in a truck's left-side and rear blind spots.

The core defensive riding stance: assume other road users may err, keep a margin of safety, ride at a speed from which you can stop in the visible distance, and communicate intentions early.

The gap to the vehicle ahead; at higher speeds it must increase so that you can stop if the leader brakes suddenly, and it also preserves your view of the road surface.

The distance travelled from the moment the brakes take effect until the vehicle stops; it grows with the square of speed and is longer on wet or gravelly surfaces.

The distance covered during the driver's reaction time before the brakes actually bite; at 60 km/h roughly 0.75 seconds of travel adds about 12.5 metres before braking begins.

Anticipating hazards by reading the road, weather, traffic flow and other users' behaviour before a dangerous situation develops, so that speed and position can be adjusted in advance.

A near-miss incident in which an accident almost occurred; recording and reviewing such events helps riders recognise recurring risky patterns in their own riding.

Emergency braking practised in the licence test: applying both front and rear brakes firmly and progressively while keeping the machine upright and the front wheel from locking.

Anti-lock Braking System, which modulates brake pressure to prevent wheel lock-up and preserve steering control during hard braking, especially on slippery surfaces.

Tyre inflation pressure; too low causes unstable handling, heat build-up and faster wear, while too high reduces grip. It should be checked cold at regular intervals.

The pre-ride and daily checks a rider must perform, covering brakes, tyres, lights, horn, mirrors, fuel and oil levels, chain condition and steering.

Periodic inspection and maintenance carried out at specified time or distance intervals, more thorough than daily checks and often entrusted to a qualified mechanic.

The statutory vehicle inspection required for motorcycles above 250 cc, renewed every two years; smaller machines are exempt but must still be kept roadworthy.

Compulsory automobile liability insurance that every registered motorcycle must carry; it covers basic compensation for injury to accident victims but not the rider's own vehicle.

Optional private insurance covering costs beyond compulsory liability, such as the rider's own injuries, the motorcycle itself, and liability above the compulsory limit.

Traffic signs erected at the roadside; 本標識 include warning, regulatory, and instruction signs, while 補助標識 add conditions such as time, vehicle type or distance.

Road markings painted on the surface, such as centre lines, lane lines, stop lines and no-parking zones, which have the same binding force as signs.

Traffic lights controlling right of way; a flashing red means stop at the stop line, a flashing yellow means proceed with caution, and a green arrow permits movement in that direction.

The white line before an intersection or crossing where a vehicle must stop for a red light or stop sign; stopping beyond it obstructs pedestrians and other traffic.

A mandatory full stop at a stop sign or line, with the wheels completely halted and safety confirmed before proceeding; a rolling stop is a violation.

Administrative penalties imposed by the licensing authority, such as suspension or revocation of a licence, based on accumulated violation points.

Points added to a driver's record for each traffic violation; reaching certain totals triggers short-term suspension, longer suspension, or revocation.

Revocation of a driving licence, which follows serious violations or excessive accumulated points and bars the holder from driving until a new licence is obtained after the disqualification period.

Removal of a restriction on a licence, for example upgrading a 小型自動二輪 licence to a full 普通自動二輪 licence by passing the required practical examination.

First aid given at an accident scene before emergency services arrive, including checking responsiveness and breathing, calling 119, and controlling bleeding without moving an injured rider unnecessarily.

Calling an ambulance by dialling 119, stating the location, the number and condition of casualties, and any hazards, then following the operator's instructions until help arrives.

Stopping blood loss by pressing directly on a wound with a clean cloth, elevating the limb where possible, and keeping pressure until medical help takes over.

Protective headgear required by law for riders and passengers; it must be properly fastened, fit snugly, and carry the appropriate safety certification mark.

Reducing the environmental impact of riding through smooth acceleration, avoiding unnecessary idling, keeping the engine well tuned, and disposing of oil and batteries correctly.