I tried to get up a small hill where there were steps to the left of me. I was almost up the hill when she bogged out. I was half way standing up on the pedals. At this point gravity took over and pushed me over backwards. Falling head first eight feet backwards into a steel hand rail with my head. Which I think broke my fall. Then slammed rearward onto the concrete steps with my head agan. Meanwhile my jaw clamped shut cutting my lip, and pulverizing part of one tooth. Also some scrapes and a 2nd degree burn on the upper inside left loin. So a concussion, split lip, burned leg, scrapes, bruising, and a Efed up grill. Lesson learned: Don't try being Mr slick on it. I Wasn't thinking about the extra weight. A helmet would be a great idea too.