79 GS850G carb baseline

[earlfor]

I would treat all four carbs as being "normal" The adjustment effect of the carb #1 airscrew is very minimal in operation beyond idle range. I wouldnt worry about it. Just do a manual synch on all four, then get #3 set to the base line vacuum value you want, and then match 1,2, 4 to that. 10 in Hg @ 1200 rpm will usually run about a light tan. 12-14 in Hg about a medium to dark tan and 16-18 in Hg burns in the brown range on my bikes.

Earl

since I can't adjust the air screw on #1 my thinking is to synch the other three to it using the vacuum carb synch tool.Comments?

[Anonymous]

Hi, all;
Did the prelim. set-up as discussed and it fired up immediately. Backed the main idle screw off to 1500 and it sounded fine. Went for a 45 min. ride, came home, reset the idle to 1100 or so and looked at the plugs. An even light tan on all four. Bear in mind these were NGK B7ES pieces-one # hotter than the stock #8 plug.They were sooty from the last go-around. I didn't play around any more today as ambient temps are 39C-105F and that's hot enough to cause beers to jump out of the fridge all by themselves. (Ain't retirement great?) Anyway, it ran pretty good except for some intermittent back-firing on the over-run in 4th or 3rd (4-6000 RPM) At this point I'm sort of at the (if it ain't broke-------) stage. Comments?

[KEITH KRAUSE]

I think you should put the B8ES plugs back in.
What do you mean by "backfiring on the over-run"? Do you mean popping during deceleration? This can be an exhaust leak or a lean condition. It could also be related to those hotter plugs you're using. I would put the 8's back in and see how she runs. If she still pops, check your header bolts. The gaskets may need replacing. If it's the carbs, getting rid of all the popping can be difficult. You can try turning the pilot screws (underneath) out a little (counter-clockwise), maybe a 1/4 turn and re-test. Keep notes so you can set them back to where they are now if needed.

[Anonymous]

Keith, popping under decel is what I mean. I concur on the plug change back to 8s and I'll check the header bolts.And yes I noted the initial set-up in writing. More later and thanks again.
Paul