I never denied being a bodger! (I'm an accountant... I'm not useless with a spanner but it's not my forte :-/)
Rear sprocket was suggested when I said it was making a grinding sound, not sure the chain was as loose as I thought now.
Seems the garages only problem was super-tightening the nut; sounds badly like rear wheel bearing now, and maybe bearing at the front sprocket too.
I think I need an expert to look at it (next step is begging phone call for father in law to bring jeep + trailer over ;D)
