LONDON - Environmentally minded British motorcycle engineers have produced a zero-emission bike that ticks all the right boxes except one- it's too quiet.  So quiet in fact that designers are looking to introduce artificial vroom to keep potential customers happy.  Powered by a high pressure hydrogen fuel cell, the Emissions Neutral Vehicle produces the equivalent noise of a personal computer fan belt.  Not only is that distinctly wimpy in the eyes of many bikers, it could also be dangerous.  50-mph machine and no gears Intelligent Energy, the company that built the prototype, is looking at ways to produce an artificial engine noise that will alert people to its presence, making sure the machine is not silent and deadly.  "We will consider that," said Nick Talbot, the project leader hired to design the motorbike.  The vehicle, which has no gears, can reach speeds of 50 miles per hour.  Motorcycle enthusiasts have welcomed the green innovation but say some bikers like the roar of an engine and the thrill of going fast.  "It fits the definition of a motorcycle, but not as we know it," said Jeff Stone, a spokesman for the British Motorcycle Federation. "The motorcycle is a primitive thing and it appeals to the inner person. The excitement and exhilaration of a bike is why people ride them."  Range of 100 miles Stone, however, believes that the "soft and cuddly" green bike could be useful in city traffic.  The bike's briefcase-sized fuel cell needs to be topped up every 100 miles and so far there is only one station in Britain that supplies hydrogen.  But its makers believe that will change.  "The whole point of the project is to say the technology is here, it works, so now put the infrastructure up," said Talbot.
Copyright 2005 Reuters Limited.