yea, i took out the tensioner, and tried to derail the chain but was getting anywhere... didnt have a 9mm spanner with me either so i just it... ill get it off today and see how i go.
Took off the inlet manifold and was surprised to see the gasket restricting a radius of about 2mm... also looks like some1 has had a go before me at the top of the port (taking apart my spare bike).
cheers