I'm no expert, and hence this could be bollox, but I thought that the front and rear cylinders have different heat rated spark plugs simply because in addition to liquid cooling, the front cylinder receives significantly more additional air cooling than the rear. Obviously much more cool air will hit the front cylinder, whereas the rear is tucked away and hence will run hotter, therefore a plug which draws more heat will be in the rear.

While I'm talking about the rear cylinder - There is a little duct which runs from the lower left side scoop on my fairing, and disappears of under the tank. Is this to get some fresh cool air to the rear cylinder - I assume it isn't ram-air, what is it