I hope this bit of info will be of use to many of you flying with Bing 54 carbs, the spares can be obtained by return service from a firm called Motorworks at Meltham in W.Yorks. They are specialist bmw dealers who stock all the bing parts,needles,jets,gaskets etc and their retail price is amazingly cheap. I have just purchased two new idle jets for LESS than one third of the cost elsewhere....I do stress that these are all genuine parts. Their tel is 01484 353600.
mike