What were you doing in the first decade of the 2000s? Whether you can remember it or not, we're going to guess that your activities didn't involve sourcing a Ferrari F355 engine to power the custom motorcycle that you were dreaming up in your head. That is, unless your name is Birger Hansen and you live in Denmark.

As he tells the story, he and his buddy Michael Anderson were drinking one day and chatting, as you do. Somewhere in the course of conversation, they started musing along the lines of "wouldn't it be crazy if we built something that no one has ever tried before?" 

Eventually, the pair of friends agreed that if Anderson could procure the Ferrari F355 engine, then noted hands-on lifelong motorcycle enthusiast Hansen would build the bike. 

Now, lots of friends out drinking at pubs have probably come to similar agreements, but not everyone sees their new project through to the end. All kinds of life circumstances often get in the way. Fortunately, though, that wasn't about to happen on Anderson and Hansen's watch.

Gallery: Birger Hansen's Ferrari F355 Motorcycle

Anderson came through with the engine, and Hansen got to work. All told, he says that he had at least 100 separate parts made by specialists just to fit his build. The F355 engine is lovingly cradled by a Boss Hoss chassis, and the whole thing has an impressively sleek and finished appearance, as you can see in the video.

Simply building the thing wasn't enough for Hansen, though. The process took around 10 years from start to finish, but he also took the time to have it type approved and fully road registered in Denmark. He went through the entire Technischer Überwachungsverein (or TUV) technical approvals process, had the F355 motorcycle certified, and paid for his registration documents and license plate like any other law-abiding motorcyclist in the nation. Except, you know, he'd built the thing himself.

It's a passion project that he brought to life with his own two hands, and that he intends to continue riding until he can't ride any longer. If you're a lucky rider, maybe you have a bike you feel that way about, too.

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