Carb Issue
Carb Issue
Hi folks. Just a quick question. Upon taking my carb apart (PW22) I discovered that someone had mixed up the idle screw and the air screw. It seems that the longer screw was put in the wrong hole and now the end of the shaft is bent like the crook of a finger. I tried to straighten it with moderate success but it will never have the perfect shape it once did. I suspect that the tolerances for that shaft fitting in the hole are pretty tight. I know I can get a kit from Tim McDowell but I am concerned that the wall of the carb within that screwhole may be damaged and a new screw would not do the trick. When taking the screw out, I observed that it was tight almost for the whole extraction. Any thoughts? Is my carb now worthless? Jeff.
1964-C77 305 Dream
2002 BMW R1150GS
2002 BMW R1150GS
They are carb specific. The idle screw has a knurled head that sticks out past the threads so you can turn it by hand. The air / fuel screw has just the slot for the screwdriver past the threads. Post on the parts wanted section, someone probably has a couple laying around.
Davo
Davo
davomoto
64 CB77
63-7 CB77 Cafe'
67 CL77
64 CL72
66 CL77 big bore flat tracker
Many others!
64 CB77
63-7 CB77 Cafe'
67 CL77
64 CL72
66 CL77 big bore flat tracker
Many others!
On my CA77, both screws are slotted heads, with no knurls on the speed screw.
It is easy to interchange by mistake.
The air mix screw (on the left towards engine) has a tapered end, and the idle speed screw (on the right toward air cleaner) has a blunt, round tip.
They should both screw in and out easily, (without the springs attached) and if not, maybe they have been cross threaded or the wrong screws used?
It is easy to interchange by mistake.
The air mix screw (on the left towards engine) has a tapered end, and the idle speed screw (on the right toward air cleaner) has a blunt, round tip.
They should both screw in and out easily, (without the springs attached) and if not, maybe they have been cross threaded or the wrong screws used?
66 dream, 78 cb750k, 02fz1, 09 wing
OK, based on that explanation my air mix screw is the one that is damaged. It is longer and has a tapered end whereas the other screw is shorter and has a much more pronounced flat tip. Thanks Brewsky. I'll post a wanted ad for the screw in the "Wanted" section.brewsky wrote: The air mix screw (on the left towards engine) has a tapered end, and the idle speed screw (on the right toward air cleaner) has a blunt, round tip.
1964-C77 305 Dream
2002 BMW R1150GS
2002 BMW R1150GS