Translation guide
In Japanese, 'electric bicycle' usually refers to a 電動アシスト自転車 (pedal-assist e-bike), not a throttle-controlled electric bike. The distinction is important for legal and practical reasons.
A bicycle with an electric motor that assists pedaling, up to 24 km/h. This is the standard legal e-bike in Japan.
The standard term for a pedal-assist electric bicycle. Often shortened in casual speech.
電動アシスト自転車を買いました。
I bought an electric bicycle.
A common abbreviation of 電動アシスト自転車. Widely understood, but technically could include throttle e-bikes.
電動自転車は坂道が楽です。
Electric bicycles make hills easy.
Short for 電動アシスト自転車. Common in advertising and casual conversation.
アシスト自転車のバッテリーが切れた。
The battery on my electric bicycle died.
A bicycle that can be propelled by a motor without pedaling. These are legally classified as mopeds in Japan and require a license, registration, and insurance.
Term for a throttle e-bike, emphasizing full electric power. Not a legal term but commonly used.
フル電動自転車は免許が必要です。
A throttle electric bicycle requires a license.
Descriptive phrase to clarify the throttle function. Useful when distinguishing from pedal-assist.
ペダルを漕がなくても走る電動自転車は、法律上は原付です。
An electric bicycle that runs without pedaling is legally a moped.
Referring to the vehicle category for regulations, registration, or official documents.
Official legal classification for pedal-assist e-bikes meeting specific criteria.
この車両は電動アシスト自転車（特定小型原動機付自転車）に該当します。
This vehicle falls under the category of electric bicycle (specified small motorized bicycle).
In Japan, 'electric bicycle' (電動アシスト自転車) legally means a pedal-assist bicycle with a motor that cuts off at 24 km/h. Throttle-controlled e-bikes are classified as mopeds (原動機付自転車) and require a license, registration, and helmet. Using a throttle e-bike without proper documentation can lead to fines or arrest.
In casual conversation, 電動自転車 or アシスト自転車 are often used. If you need to be precise, use 電動アシスト自転車.