Motorized bicycle legal?

devnull

Cruising
Aug 14, 2013
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Is putting a 47cc gas engine on a bicycle legal here in Japan? I'm thinking about building one up for my daugther. I'm in the boonies of Aomori-ken in case that matters.
 

Half-Fast Mike

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May 22, 2007
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It's possible to do it legally, but probably more hassle than you want. Doing what you suggest would make it into a literal gendoki-tsuki jitensha, that is, a bicycle with a motor on it, which is a moped or scooter.

I believe a roadworthiness test would be required before it could be used on a public road. The rider would certainly have to have a driver's license and wear a helmet. The vehicle would have to be registered, have a number plate, lights, and turn signals, and the jibaiseki compulsory vehicle insurance.

If it will only be used on private land, then forget what I just said and have fun!
 

jdd

Maximum Pace
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Jul 26, 2008
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Go electric, e.g., one of those oversized rear hubs with a motor built in, and you'll remain within the world of bicycledom, legally.

Just curious, but how old is your daughter?
 

devnull

Cruising
Aug 14, 2013
38
12
18
51
She's 13.

She's not into cycling beyond the occasional haunt around the neighborhood. She likes the idea of a motorized bicycle mostly for the novelty of it all than from the standpoint of transportation. I like tinkering with things so the idea of installing a gas engine is appealing.

I'll probably end up doing it. We are in the middle of farm land, there are plenty of rice field trails all around.
 

baribari

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May 28, 2010
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FWIW, you have to be 16 to get a moped license.

But on the other hand, you're not legally liable for anything until you're 20, so....