We go back and forth across the border with bikes regularly - flying and by car.
In 20 years of doing this, I've only really been asked about the bikes and their origin ounce - coming back into Canada (I'm Canadian). I had my bike as it is normally when we travel by car on the roof rack. The Canadian Customs/Border agent started in with the 20 questions about the bike - where was it bought? Did I have a receipt? . .etc . . My answers apparently were not good enough, so I was pulled over into Secondary. Met with another agent there, who asked me to take the bike down off the car, and again he's asking for receipts, and wanted to search the rest of the car. No sooner than I had the bike down off the roof-rack, when there was a massive amount of commotion in the Secondary area, and a whole bunch of Agents swarming another vehicle parked a few cars over from me. As I'm standing there with my bike in my hands, the Agent with me, says "You can go now", and he darted over to the other car with all the action, and that was the end of that!
Steve Fleck @stevefleck | Blog