Well Baz my original Amals were zinc pot metal and were completely flogged out at 35K miles I replace them with new Amals in 1979 brought through the Queensland Norton owners club so they did the order, the new ones were a different lighter colour to the old Amals so not sure who they got them through, they are more alloy than zinc in colour.
I have done over 80k miles on these replacement Amals and so far the slide aren't flogged out like the original Amals, in fact they not even lose in the bores only where they slide easy up and down in the bores, I did replace them 14 years ago (when I was having a running problem with the Amals)) with new PWK carbs from Jim when I had spare cash at the time, I was doing other upgrades at the time on my Norton, but as I have said I had troubles with left carb having sticking float so decided to go back to the old Amals.
Before putting them back on a full pull down and replace the jets, needles and idle and air screws and found the left pilot jet passage was fully blocked (so was the cause of my running problem before removing them) after 2 attempts of soaking and poking finally got it unblocked, I also got my mate Paul who is an old Triumph man and Amal person to check out the Amals before putting them back on and he couldn't believe how good they were in the slides, he also knows the full history of my Norton from the first day I brought it new in 76.
I also owned a new 81 Triumph Thunderbird with a single Amal carb on it I clocked up 250k kms on that bike and when I sold it still had the original Amal on it, but the same thing jets and needle were replace every 3 years of service, but the slide was always good, so whether Amals did change to better metal long before 2012, who knows, all I know is my old Amals are fine with very little to no wear on the slides, lucky, freak of a bike, who knows.
My Norton was an everyday rider most of its life till 2013 when I brought a new Thruxton 1200 so now its semi retired just like me but still gets ridden regularly and its running without missing a beat with the old Amals and idles great with the Joe Hunt maggie.
Ashley
