Piglet - should have guessed this was you really shouldn't I! My powers of deduction aren't as good as yours evidently.
Anyway.
Did you leave the bike with fuel in the tank? If so, that may be the problem. If left, petrol evaporates but leaves behind a gummy residue in your carb jets, meaning your newly gleaming plugs aren't getting any fuel to ignite.
As previously mentioned though, it may just need bump starting to get everything moving again.
What you need is the special tool known as a 'Dave'. I'll pop over and get it running.
8-)
