i didnt do it riding trials, but i "shaved" my entire chin off when i fell with my courier bike, i shaved my whole chin all the way to the bone. what made it worst was that i also scraped both my shoulders and hands on the pavement. i didnt know at first that i hit my chin beacuse my shoulders hurt more. so i got up and rode 10-15 feet and noticed that i was dripping on my handlebars. (for those faint of heart: stop reading now) anyways so i stopped and touched my chin with my already roadburned hand and felt nothin but bone, yeah it hurt!, so after noticing to myself that 1)i and shaved my chin of all skin and 2)that both my hands and my shoulders were severly road burned. all of this happened 2 mi away from my house with no other houses in sight. but i maneged to get back home bruised and beaten to take a shower and get cleaned up, only to realize nobody was at home! so i waited around for about and hour until my sister got there which when she drove me to town to the hospital...so yeah theres my story, i still have a wierd scar on my chin from the wreck, o one more thing 2 weeks ago i got hit couriering by a lady who ran a stop sign...that hurt aswell!