Here's a quote from him in Rolling Stone Magazine about that wave.
"There I was on a motorcycle, with the worst thing that could possibly happen. I turned out from the wave and it crashed down behind me, chasing me down. I was picked up and thrown, and my bike landed on my back, knocking all the air out of me. It was the most violent ride I've ever been on, tumbling beneath the surface in full gear. Over the next four or five minutes, I only had two split-second moments when my head broke the surface and I could take in a fast breath, only to be yanked back down and tumbled with my bike. Everything was going white. I became completely limp and was prepared to take in a full breath of water, when I finally popped up. I could see the helicopter and Jet Skis, and had a quick moment to wave my arm so that they could locate me."