u/AlexHimself

Video - https://www.reddit.com/r/sandiego/comments/1sxtmnw/just_walk_it_off/

Another user's math claims 47-55mph, but that seems too high from just eyeballing it. I'd guess 37-43mph -

> The motorcycle enters the video at frame 105 and impacts the car in frame 124. So, in 19 frames (about 0.63 seconds) he traveled about 3 to 3½ lengths of the car (1996–2000 Honda Civic coupe). If that car is 175 inches long, he traveled between 525 to 612 inches in 0.63 seconds, thats ~47 to 55 mph.

It seems that 55mph is just way too high of a top-end.