Here is a collection of pictures I hope are instructive. These are all in reference to carburetors, some things that just happened, others that happened to them. Take heed.

This is a classic! Folks unaware of how to remove the SOHC four throttle shaft pound on it and damage the shaft's locating groove.
 

Here is where they should have started, by removing the pressed-in pin. The screw shown has taken the place of the locating pin.

This idle jet from a VB series carburetor shows why it needs to be removed even though it requires unusual means.

Welding of float pivot posts is a frequent need on vintage carburetors. It takes a specialist. This is not standard welding.

Thread repair in the form of steel thread inserts is also a common part of carburetor rebuilding.

 

That's a lot of rust on that float valve screen. Some people advocate leaving these screens off. What do you think?

These float pivot pins have been mangled by the use of pliers. It's best to replace them because the divits will stress the pivot posts.

This accelerator pump passage tube has been broken through unprofessional carburetor disassembly technique.

Air cutoff diaphragms are easily damaged when someone tries to clean carburetors without first removing the diaphragms.
 

This is a Gold Wing carburetor throttle shaft that has been twisted by an impatient user.

The vacuum fuel valve often found on Honda carburetors can fill up with muck.

This VB series constant velocity carb shows evidence of deposits from the crankcase recirc system.

Yes, that is a pilot screw sticking up inside the carburetor bore. Hopefully the screw has not broken off inside.
 

Too bad. Here is the screw missing its tip. The left behind tip is very difficult to get out.

This is how most CB500/550 and CB350/400F carburetors look. This can be saved.

This is a GL1000 carburetor. It is too eroded to save. The carb body must be replaced.

Someone used heat on this GL1000 carburetor, already ruining it. Then they tried drilling the idle jet tower. The carb is junk.
 

That's rust inside that fuel inlet cavity. Ultrasonic and hand work will get it out.

This cracked overflow standpipe is extremely common on Honda carburetors. There are two different methods for repairing this.

If the crack is small enough it can simply be soldered closed. This works well 80 percent of the time.

One or two judicious raps with the plastic end of a screwdriver can solve carb overflow. Repeated hammering with a metallic object...
 

This is a very common thing on CBX carburetors. It results from prying the carbs in the wrong place. Expensive part.