So, apart from being an amazing feat of engineering, what's so special about this? Well, The Daily Mail reports in typical disregard for science that:
"The bike's makers claim that the G-force which the rider has to contend with is three times more than that faced by a skydiver during freefall."
G-force is a unit equal to the force exerted by gravity. It gives weight to a mass. The other way to look at it, is we are all being accelerated towards the earth by 1G (although strictly, that depends on where on Earth you are). 1G is about 9.8m per second (every second).
A skydiver in free-fall reaches a terminal velocity at about 120mph (200kph) due to wind resistance and never experiences any more g-force than if he were sat in a chair. The equations of motion for an object under constant acceleration, accelerating from a standing start are as follows:
The bike covers the quarter mile track (about 402 meters) in 7.8 seconds giving an acceleration of 13.2 ms-2 which is well below the brain-busting 29ms-2 acceleration claimed attributed to KillaCycle. There is something I'm ignoring here and I'll come back to that before you jump in and comment on it, but if KillaCycle really was achieving such acceleration it would travel nearly 1800 metres (over a mile) in the time.
So where does that come from? Clearly, KillaCycle is not accelerating constantly for the entire quarter mile. The 3G experience comes in the first shoulder socket-wrenching second and it's likely that most of that happens in a small fraction of a that second.
Cars, planes, motorcycles and pretty much everything that accelerates under power do so variably - the acceleration curve: but the Mail isn't interested in that and just runs the quote from the release.
Perhaps more interesting though is the boast that a four minute charge from wind energy is enough to power the vehicle (they claim) for seven runs. The energy may indeed by "green" but you can bet your CO2 emissions that those batteries are about as recyclable as George W Bush is climate aware
However, let's take nothing from the achievement, even if it is a bit of a white elephant. KillaCycle's team are now said to be working on a 1000BHP version. Presumably the Mail will be telling us next that it's twice as fast too.
In other news, someone stole my shaving cream so my face is sore.
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