I have had a go at derestricting the bike today, got all of the speedo apart to find that the speedo mechanism doesn't have the tab inside? Looks like it has had some sort of replacement from a different set of clocks. It has got a little box attached to it with a brown and an orange wire plugged into it? The bike revs fine and has recently been rejetted so I'm unsure as to what it could be?
Here's the box:

Thanks,
Luke