I recently discovered that one of my float needles is now showing a problem that is causing my left cyl to be lean. My first look into replacement was quite a shock, Triumph is the only source for the float needle and they are 40+ bucks each. Ouch. The CVK carb is the one I am refering too, it was apparently made specifically for Triumph. I have now found a source for replacements and a bit of info I would like to share. The metal (aluminium) these float needles are made from has an issue with the additives in US fuel causing them to break down, mine is actually peeling. A carb specialty shop in Georgia has not only explained this issue but has a stainless steel replacement for 11 bucks each. They also have the hole kit ( bowl gasket pilot needle float needle and spring) for 26 bucks, the float needle is the original alum version you have to get the stainless ones sepparately. Great guy, very helpful, and gobbs of carb kits. Here is the link.
http://www.motorcyclecarbs.com