Yamaha is the only company running an I4 in the MotoGP series, a layout to which it has been loyal since the inception of the current four-stroke formula; all the other engines are now V4s. Having the cylinders in a vee, rather than in a line, allows the crankshaft to be shorter and stiffer, with fewer main bearings, and the engine to be narrower. This is, however, perhaps not such a great advantage. The reasoning can be found in the width of the human knee. Complete with protective...

Pollution would seem to be an inevitable result of 21st-century life. Sulphur dioxide, nitrous oxides and PM10s are destroying the quality of our air; industrial and farm effluent together with excessive use of fertilisers are contaminating our rivers; and general domestic waste, used for landfill, are all visible sources of our times. However, one source of pollution - not quite so readily observed and not generally recognised as such, but increasing daily - is that of electromagnetic...