The entire float chamber assembly on later Three-Jet Binks carbs is identical to the Amal one, so float needles are readily available, but be sure to specify that it is for a top feed type chamber. With the earlier very heavy bodied Binks, with a zinc float chamber top, that has “Binks 1920 Eccles Ltd” cast into it, you are out on your own as regards spares.
Your mag should be able to produce audible, cracking, blue sparks over a 1/4″ gap. Anything less than that, yellowish, and nearly silent, is suspect. I highly recommend the book “The Vintage Motorcyclist’s Workshop” by ‘Radco’ (Frank Farrington). It explains how to make a simple spark gap testing tool, plus lots of other very useful tips.
Brian
