Ah, dating is not defined the same way it was when you and I were in our teens and twenties. Bike Dude #1 likes you. And, he may even think (in his mind) that you are dating, by modern standards.
This still doesn't explain the body language, and as Irulan said, it's probably not worth trying to figure it out. Personally, I would enjoy the attention, unless, of course, you really don't want it (like the 12 texts). You need to set boundaries if you don't want him doing stuff like that. You're in charge!