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So does anyone no for definate if you need to have the number plate light for MOT??

I was told during an MOT a couple of years ago that my numberplate light was U/S..then he said it wasn't required anyway as it wasn't on the test items for a bike.
Maybe it's changed since then? Ring an MOT station and find out.
Richard

Remember the discussion a few weeks back about whether you had to have indicators / lights on your bike? This came up in connection with riding trackday-only bikes on the road. You wouldn't fail the MOT if you take off the indicators, etc, but the concensus was that although an item isn't part of the MOT test, it is still required for the vehicle to be road-legal. I imagine the number plate light falls into this category.