Andy, you have been stalking ALL DAY! (Only 'cos I have been watching your posts)
As the weather forecast is set to be blisteringly hot this Sunday, how about doing a bit of the Park and Ride ride? It will involve mooching from the bogs to Marble Arch, Oxford Street, Wigmore...Portland Place, toward Camden, Kentish Town - up to the Park and through, sod about in Hampstead, climbing the hill (or x country if preferred - over the Heath?*) Then a touch of Spaniards to Bishops Avenue - a quick up and down, returning via Primrose hill and Regents Park, Edgware Road - then Lo! Hyde Park, where adieus will abound.
I reckon 90 minutes or so for that.
Or we could hang around chatting - I'm easy (always been my problem
)
*A little bit gravelly - not much though.