I nearly did that driving to the start of the Savage Century in Delaware. The start location was at the Gore R&D facility. It was a new starting location for the ride. The club running the ride gave people directions that routed people under a very low railroad overpass. Just as a I entered with my large, custom IF on the roof, a wave of terror swept over me. the GF got in the driver's seat (her IF was small) and slowly piloted the car forward while I walked along side to make sure there was enough clearance. My heart was still pounding when I got to the registration table. When I got home, I measured from the top of the saddle down to the ground. The height was 2" less than the marked clearance.

Later that week, the GF emailed the club running the ride. A representative was quite receptive. The next year there was a warning in the directions about the low clearance for people thinking of taking the route to the start.