I have an oil leak coming from somewhere at the front of my YB on the top end, I think it could be cam seals or rocker, but there are two allen key headed screw type things behind the cam pulleys, can these leak oil as they do look like they could be the problem? any information would be good.

Thanks

 

more than likely the cam seals mate

 

Those grub screws are tapered plugs for closing up the oilways after manufacture.
There is oil behind them so if they look suspect then remove them,clean them up and refit using a quality thread seal,not thread lock as that's a different product altogether.
But I'd suspect the half moons or cam seals.

 

As above or the area between the head and front cam cap.
these get often overlooked.