For those of you with early 70's carburetors, you might have leaf springs that hold the jets in place inside the float bowls. They look like thin metal propellers that hang below the floats.
They are not easy to find and can ruin your day fast. Usually, it comes down to trolling the forums for one or buying a set of carbs off ebay and praying they have some.
User thegabrielj, however, brilliantly suggested using a hacksaw blade to fabricate a new one. I made about four last night and my 1976 Honda CB550 has never run better.
Attached are instructions.
Things to keep in mind:
-You don't need the forked "tongue" like the original. It's too hard to fabricate and as long as your fit the bowl straight, you'll be fine.
-You may have to adjust the float itself to compensate for the new tension.
Good luck!
UPDATE:
I had to do some carb work and remembered to grab a few shots of what the original leaf springs look like:
