Topic: Air mixture screw..

[surein]

hey so I'm trying to follow the manual and it says one full turn - is that a full turn loose from the screw tightened all the way till the spring compressors? Please say no cause that's what I have it and the bike idles at 5000rpms. Just want to know there's nothing significantly wrong with my bike.

It ran well with 3 turns from full tightened but I think it's a bit rich cause I get a little bit of back firing when I blip and throttle to a lower gear.

so I have this backwards?

It's a 73 CB750

Thanks

[CycleRanger]

Seat the screws lightly all the way in. 
Back them out one full turn as a starting point and adjust from there.
The further out the screw the leaner the mix.

See this thread: http://forums.sohc4.net/index.php?topic=5410.0

Have you done a carb sync?  If not you may not be able to get it to idle smoothly.

[Fritz]

is that a full turn loose from the screw tightened all the way till the spring compressors? Please say no cause that's what I have it and the bike idles at 5000rpms

Could you confirm that you really know the difference between "idle screw" and "air mixture screw"?
There are four air mixture screws (one in each carb) which have to be adjusted one after another on a warmed up motor until you get the highest idle.
The idle screw is used afterwards to adjust the idle speed back to about 1100 rpm.

Reading your post, I've got the impression that you mixed up idle and air mixture screw...

Cheers
Fritz

[surein]

frak! there's more than one screw? I need to read this book again

[Johnie]

This should help you out. My pinky is pointing to the idle adjustment screw of which there is one which adjusts the idle on all 4 carbs with that one screw. My index finger is pointing to the air mixture screw of which there is one on each carb. The other small screw you see between the two is the sync port for your vacuum gauges if you want to sync the carbs. Click the pic to enlarge it.