Hi, this might seem like a really daft question but I'm a complete beginner, I have excessive amounts of black fluid dripping from under my exhaust. I have removed it today to have a good look and when I look through the silencer I seems I have some tissue in there. Is this normal ? Thanks

Sounds like unburnt two stroke oil and the exhaust packing is breaking up.

 

Well I have removed the tissue and slight bit is still leaking putting that down to build up. The bike has got a lot louder with slight popping noise. Also my clutch seems to be really grabby but after that little ride it seems to have got a lot better 

The packing you have removed acts as a silencer, so you need to repack with new packing. Before re-packing, blow a heat gun through the exhaust for a few minutes, it will heat up and burn off the oil.