Originally Posted by Koyote

Watch the video closely, and it appears that sealant sprays out of the tire (onto the road) when it goes out from under him. But it was already flat -- his mistake was not stopping immediately to get his backup bike.

​​​​​​By the way, he stated that he hit a pothole and damaged the wheel. Nothing would've held up to that -- he would've been doing a bike swap with any type of rims.