The guy’s Dad wrote this http://www.classicbikeforum.com/forum8/2532.html
Regardless of what the lad was doing on his bike, the cheese wire should not have been used as a barrier IMO.
The more I hear about that "cheese wire" the less I like the sound of it.
It also sounds like his front end snapped, sure sounds like a design flaw to me.
The wire on the side of the road is bad news, bad enough when its barb wire fences or the like put up by private owners, over here though his father would have a good case against the government for putting up the wire.
As far as a "design flaw," its not. His bike was engineered to do very specific things, as all of our bikes are. Aluminum frames, whether they be on airplanes or bicycles, have a "life span." Aluminum is stiff, more so than steel, and as a result of repeated shocks hardens and fractures, just like any metal will over time. As performance becomes more important, the search for lighter, stiffer frames shortens the lifespan of the frame. For example, many parts of military aircraft are inspected after each and every flight. Others have to be inspected after certain loads measured on g-meters (a 10g force on a F4 phantom used to require both engines to be pulled and serviced with a complete airframe inspection). The closer to the "safety margin" a given part is engineered, the shorter is life span will be and the more frequent the inspections.
Our motorcycles are much less overbuilt than they used to be, so for those of us that race or stunt, we are pushing up against the life span of our machines much sooner than before. Landing hard after a wheelie is a significant impact! In fact, if you asked the engineers of the frame, I'm sure they could tell you the number of times you could do that before the frame failed, and I would suspect its a much lower number than most of us would think.
The real factor is ignorance of how closely to the safety margin our bikes are engineered. I know very few people that would replace their frame based on the number of miles on their bike. But there
is a number of miles after which the frame designers would tell you to replace your frame, even if on the outside it appeared normal, and its probably not as many as we might like to think. An aluminum framed bike will not be good forever, and how its used will decide how long the frame lasts before failure.
