I just got pulled over by a cop

Quick background. We just had two of our old foreign teachers finish their contracts two weeks ago and two new ones come. Although I already had a bike (it was a small, fold-up one with tiny wheels [read = slow and sweat-producing]), I bought a regular-sized bike, with a basket, from one of the outgoing teachers. I then sold my small bike (at quite a bargain price, to be fair) to one of the new teachers.

So the new coworker who bought my bike lives one station north of me, which is fairly close (maybe 5 minutes by bike, 15ish walking). So he came with me to my apartment tonight to pick up the bike, and then, because I know the area better, I went with him (both of us with bikes now) to show him how to get to his station from my place. And afterwards we got dinner and drinks at an izakaya.

So then after dinner, a little before 1:00 a.m., I am biking home and I pull up at a stoplight right after I pass a cop. He then walks over to me and we have the following conversation [in brackets = conversation in Japanese]:

Cop: [Do you speak Japanese?]
Me: [A little]
Cop: [What's your name?] your name?
Me: (I dismount my bike and say my name)
Cop: (pointing at the registration number on my bike) [Is this bike registered in your name?]

Important sidenote:
1. Bikes must be registered in your name and police officers sometimes stop people to ask this question to help prevent bike thefts. They also sometimes ask stop foreigners to ask to see their Alien Registration Card.
2. I still had not changed the bike registration from my previous coworker's name to mine.
3. From what I understand, it is illegal to drink and ride your bicycle here, and there is a zero-limit for alcohol. Although I was not drunk, I did have a beer and some sake.
4. Throughout our entire conversation, people are passing by and staring, trying to overhear why the cop has stopped the gaijin.

Me: [No. My friend.]
Cop: [What is your friend's name?]
Me: Sarah Johnson*
Cop: [Where is she?]
Me: [Saitama (the prefecture north of Tokyo).] She moved two weeks ago. [work]. We were coworkers... [I bought the bike (although I used the wa particle instead of the o particle, so I said this sentence a bit wrong)]
Cop: ?
Me: [I bought the bike...]
Cop: ?
Me: [bought... buy... I bought the bike.]
Cop: [Whose name is the bike registered under?]
Me: Sarah.

The the cop radios some station, gives them the bike registration number, and they respond back with the name. But it sounded kinda fuzzy, and I'm not sure he could really make out the name anyway... So at this point, he looked slightly perplexed as to what to do.

Cop: [Bike] something something something
Me: [I'm sorry. Bike?]
Cop: [Bike] something, something, something
Me: [I'm sorry. I don't understand.]

pause while he contemplates what to do.

Cop: [Can you call Sarah?]
Me: [Yes. On my cellphone?]
Cop: [Yes. Or is it too late?]
Me: [I don't know.] (knowing actually that yes, it was too late and she would be asleep...)
Cop: [Does Sarah speak Japanese? Sarah] do you speak Japanese?
Me: [Yes, she speaks Japanese.] Should I call?
Cop: [Yes.]

I call, but it goes straight to her voicemail, thankfully. However, he could at least see Sarah's name come up on my cell phone. And then I tried to call again to let him listen to the voicemail, but he didn't seem to want to listen. So then we are stuck again.

Me: [I'm sorry... Do you understand English?]
Cop: [a little]
Me: (pausing frequently, talking slowing, and using some gestures) Sarah and I worked together... [work.] Two weeks ago, she finished work. She got a new job in Saitama, two weeks ago. [I bought the bike. But,] I need to change the registration.
Cop: pause as he contemplates what to do. [It's okay. I'm sorry. You can go.]
Me: (bowing) [I'm sorry. Excuse me.]

And then we both rode off rather quickly, I think happy to do be done with our awkward, attention-creating exchange.

Anyway, so that all turned out okay, I guess. But I was really nervous that 1. he was going to confiscate my bike or 2. I was going to get in trouble for drinking and riding my bike. Add onto my nervousness the fact that all this took place at the crosswalk of a fairly busy traffic light (considering the time) and at least 10 people went by sticking their neck out and staring, curious to overhear why the foreigner was being stopped by the cop. I think I spoke just enough Japanese to explain what was happening, kind of, but not enough to be able to understand him tell me what I was doing wasn't allowed.

Moral is: register your bike and don't stop at crosswalks near cops on unregistered bikes.


*I changed my coworker's name.