rich all 4.

[i57chevy]

I have a 1981 gs750l with the air screws on top near air filter. which way do I turn them for rich or lean? all four are running rich with smoke. I've been battling this bike with issues since I got it. I replaced the petcock. adjusted the valves. adjust tooth timing. rebuilt carbs. checked for leaks replaced exhaust gaskets. among other.

[Nicholaschase29]

out makes it richer in makes it leaner. It may be a problem bigger than just turning a screw :-D. You may need to do some serious jetting.

[i57chevy]

I was wrong about location of screws. Been awhile since I messed with this prob. I'm pretty sure that they weren't all running rich before the carb rebuild. should I do another sync with them at 1.5 out. what comes first?

[bradleymaynar]

I'm not sure of the exact #, but I believe that 1 and a half to 2 turns out from all the way in is normal for a stock air box and exhaust. Once you get this setting figured, you should use a manometer to synch the carbs.

Brad bt

[i57chevy]

thanks. I'll try better.

[i57chevy]

fine tuning the air screws wouldn't throw the sync off after?

[bradleymaynar]

fine tuning the air screws wouldn't throw the sync off after?

I don't know for sure, but after a carb rebuild it is necessary. If you've already synched them, it couldn't hurt to check after adjusting the air screws.

Brad bt

[Nicholaschase29]

I was just syncing today adjusting the mixture screw wont change sync unless your really far off. If you just moving it < (less than) 1 turn you should be fine

[bradleymaynar]

I was just syncing today adjusting the mixture screw wont change sync unless your really far off. If you just moving it < (less than) 1 turn you should be fine

That was kind of my thought, but with his situation it might be advisable. Besides, it's a fairly quick process IMO. VM carbs, on the other hand...

Brad bt

[i57chevy]

thanks for all the help. after I moved them to 1 and half. I ran it in the yard for a few cut it off at idle and checked one plug. It was obviously still sooty, but it looked like it was trying to tan up a bit. I quit cause it was getting dark.