All my gaskets and seals came today so I got the engine built back up. You can slightly hear the worn tooth on idle but on throttle it's completely gone. I think the clutch may be slipping but Iv still to test it. I also need to replace the small end bearing but so far so good on my £180 bike . Iv got a video of before and after if anyone is interested. It's YouTube links
http://youtu.be/nivHDCwonQ0 (before)
http://youtu.be/p2rWbHlHeUk (after)