Just strip em down and get some grease in once in a while.
Yea I did that.... Just don't drop the roller from the bearing into the lawn. I ended up having to buy new wheels for that reason.
I'd like to say this issue is fettled, but Halford's cocked up and despite click and collect saying the mech was in-stock, then sending me a text to say it was ready for collection it turns, after 35mins of hunting around the shop it never was in stock. At 09:30 when they first discovered this it did not occur to them to order one for tomorrow. so I will not be available until Friday PM.
Hanger is definitely bent, but getting the correct new one is proving more difficult than first thought. It appears only Winstanley's stock them, unless anyone can ID. Bike is a Ridgeback Flight 01 - 2013.
And yes, the chain has been off the bottom of the small cog. If you look carefully you can see the ripples where the hanger has bent :-( I think I am lucky to have got away without damaging spokes.