A , sometimes referred to as a heavy motorcycle, is a category of motorcycle defined under the Road Traffic Act of Japan. It refers to motorcycles with an engine displacement of over 400 cc or a rated output exceeding 20 kW. A specific driving licence is required to operate such vehicles.

Other categories include a small two-wheel motor vehicle (small motorcycle) and a standard two-wheel motor vehicle (ordinary motorcycle).

Heavy motorcycle licence

A licence to ride a heavy motorcycle can be obtained from the age of 18. An automatic transmission (AT) licence restricts the holder to automatic motorcycles, whereas a manual licence permits operation of both automatic and manual motorcycles. Riding a heavy motorcycle on a public road without the appropriate licence constitutes the offence of unlicensed driving.

Licence category history Heavy motorcycle and ordinary motorcycle licences have been separate categories since 1996.

In June 2005, it became possible to ride automatic transmission motorcycles exceeding 400 cc with a heavy motorcycle AT licence.

In December 2019, the displacement limit for automatic transmission heavy motorcycles was removed, allowing operation of motorcycles of any displacement with a heavy motorcycle AT licence. This change applied both to newly issued licences and to existing licence holders. From the same date, motorcycles powered by electric motors or other non-internal combustion power sources have also been classified as heavy motorcycles when their rated output exceeds 20 kW.

History of the 750 cc distinction Historically, heavy motorcycles in Japan were commonly referred to as (literally, "seven and a half"), reflecting the widespread 750 cc displacement limit.

This originated when the Honda CB750FOUR was introduced, as its performance exceeded . The National Police Agency, concerned about high speeds, requested manufacturers to adopt a voluntary limit restricting motorcycles sold domestically to 750 cc.

As a result, manufacturers such as Kawasaki motorcycles developed models like the Z2, a reduced-displacement version of the Z1. Similar adaptations were made across the industry until the mid-1980s.

The voluntary restriction was abolished in 1988, after which motorcycles with engine displacements exceeding 1,000 cc became widely available in Japan. However, some practices influenced by the earlier distinction remain; for example, ferry transport fees may still vary depending on whether a motorcycle's displacement exceeds 750 cc.

Categories Some of the vehicle categories under Japanese law are as follows: NameJapaneseDescriptionMopedAny motorcycle with engine displacement of 50 cc or less.Small motorcycleAny motorcycle with engine displacement over 50 cc but no more than 125 cc.Ordinary motorcycleAny motorcycle with engine displacement over 125 cc but no more than 400 cc.Heavy motorcycleAny motorcycle with engine displacement over 400 cc.

Other details Licence typeMinimum ageDisplacementLoading capacityLegal speed limit (general roads)Expressway ridingPillion ridingBus lane ridingMoped16Up to 50 ccNoNoYesSmall motorcycle (incl. AT)16Up to 125 ccNoYes (1 year after licence acquisition)NoOrdinary motorcycle (incl. AT)16Up to 400 ccYesYes (1 year after licence acquisition)NoHeavy motorcycle (incl. AT)18No limitYesYes (1 year after licence acquisition)No

Applicability in other countries Great Britain has a licence exchange agreement with Japan (and several other countries and regions), allowing holders of a Japanese large motorcycle licence (大型二輪) who are resident in the United Kingdom to exchange it for an equivalent British licence (Category A). Applicants must submit their licence, an official translation, an application form, and the required fee to the Driver and Vehicle Licensing Agency (DVLA), or to the Driver and Vehicle Agency (DVA) in Northern Ireland.

Gallery

See also Bōsōzoku Mopeds in Japan Small two-wheel motor vehicle (Japan) Standard two-wheel motor vehicle (Japan)

References

External links Information about acquiring a licence (Japan Motorcycle Promotion & Safety Association)