Author Topic: How to Adjust Air Screws? (Read 2967 times)

NintyOne · « **on:** June 02, 2006, 07:14:01 PM »

When I drilled out the air screw plugs, things seemed to be a little gummed up in there. I noted the position of each screw, and then proceeded to count turns until full bottom. I got 1.75, 2.15, 2.2 and 2.2 turns for #1~4 respectively.
Now everything is cleaned up and back together. I put the air screws exactly back to how I found them. The bike is fired up and although idle quality and stability has improved noticeably, I still can’t achieve a good solid balance no matter how I try.
So, I am beginning to think that I must ensure proper air screw adjustment first. What is the best systematic way to go about this?

TIA

gsxr400 racer · « **Reply #1 on:** June 04, 2006, 09:59:53 AM »

screw them in till lightly seated then back them out 2 1/2 turns to 3 turns out the deal is sometimes when you drill them out your drill bit hits the screw and moves it so that maybe why your were so off!

PitterB4 · « **Reply #2 on:** June 04, 2006, 10:07:12 AM »

I don't have my manual in front of me but I believe it states that the factory setting is 1.75 out. Of course, it also states that they are highly technical and set at the factory and that you should never touch them.

NintyOne · « **Reply #3 on:** June 06, 2006, 11:51:46 AM »

Well, I didn't drill through the brass plugs. I simply enlarged the existing holes, without going all the way through, large enough to get a #4 sheet metal screw started. Then I pried out the plugs using a pair of needle nose pliers. So, I am certain the air screws weren't disturbed.

As far as the fix, since a run time readjustment wasn't very fruitful (limited access into a hot space), I just readjusted all four to 2.2 turns out and the bike is running 10 times better. The off idle hesitation is completely gone. Off course, in part, this may be due to the fact that with a more healthy and stable idle I was finally able to properly re-balance the carbs.

Regards