emission jets and air screws

[oldtimer]

I own a 1978 GS1000C. I have owned it for 20 years. This past winter I made the mistake of leaving ethanol laced fuel in the bike. The petcock that has worked perfectly 20 years, decided it was time to leak. This kept fuel in the carbs.This spring when I tried to start it, it coughed and gagged finally running on 2. I knew immediately what was wrong as this happened to me on another bike, a GT550
So I pulled the carbs and cleaned all the coagulated funk out of the mains a severely clogged pilot jets and all the passage ways. I am ready to put the carbs back on and I have 2 very pointed questions.
The emission jets on the carb bottom were removed when I first got the bike. I didn't think I could do a good job of cleaning the carbs with those in place.. I checked these emission jets before I pulled them out this time and they were all over the place, ranging from 3/4 to 2 1/8 turns out, Equally, the air screws were all over the place as well. They ranged from 1/2 to 3 1/2
So my question are, is there a base line / ball park setting for the emission jets. and how much effect do they have on the actual tuning of the carbs? Also is there a base setting for the air screws?

I should mention the bike had a dyno-jet stage 3 installed about 7 years ago. It was 'professionally' tuned at that time. Hasn't run all that well since. Also running pods Bike has 26,560 actual miles and has never been opened.

Thanks

[chuck hahn]

this is what you need..

http://members.dslextreme.com/users/bikecliff/images/vm_carb_rebuild.pdf

Bottom pilot scrrews are at 3/4 to 7/8 out and left alone after that. Side mixture screws are where the adjustments are made and set at about 2 out as the starting point. youll probably get the best performance with them at around 1 1/4 to 1 3/8 out though.

[tkent02]

I should mention the bike had a dyno-jet stage 3 installed about 7 years ago. It was 'professionally' tuned at that time. Hasn't run all that well since. Also running pods Bike has 26,560 actual miles and has never been opened.

Thanks

To get it right is going to take more TLC than any professional shop is going to do. DIY thing for sure. You didn't mention your elevation, which exhaust you are using, what type of pods, K&Ns or some Emgo "Sand Sifters"?

Chucks settings are probably a good place to start if you are somewhere near sea level.

[Guest]

What main jets did they put in the carburetors, the kit came with two sizes.

[oldtimer]

You didn't mention your elevation, which exhaust you are using, what type of pods, K&Ns or some Emgo "Sand Sifters"?

I believe the elevation here is 720. The exhaust is an unknown 4 into 1. Was a rusty mess when I got the bike. I had them ceramic coated but there is no name. Center stand is retained might be a clue. Pods are el cheapo sand sifters
Dyno-jet kit still has the 142's in the box, so the 138's are in them.

[JTGS850GL]

Funny, I don't see any pod filters on that bike. Start as Chuck stated and tune from there.

[Guest]

That sure seems to be a stock air box unless it's been modified inside. Looks like they should have put a Stage-1 jet kit in it.

[oldtimer]

It' wasan old photo. Probably late 90's. 3 trips of taking the carbs off and on with the stock air box is enough to cure anybody. Stuck on pods and sold the stock system on eBay. Spokes got rusty and I stuck 79 mags on it. Here's a more recent photo. I prefer the spokes but can't find them anywhere. Contacted buchannan but they never responded.

[hannibal]

Beautiful bike! Is that a stock paint scheme?

[Guest]

Try the 142 jets with the Pilot fuel screws starting at 1/2 turn out and the air screws 2 turns out. Chucks recommendations are good for a stock setup but a little too far out for the larger jets. If I remember correctly the main jet needle clip position was the third from the top but my memory isn't very good these days. I saw the paper I had the setting on just the other day but can't find it at the moment. I'll find it or call Dynatech tomorrow and post it. My Pilots fuel screws were a little lean so I had to tweak them out about another 1/8 turn to cure a low speed stumble at about 25MPH through town. I get 44MPG on a regular basis and it is very smooth.

[Guest]

I have a set of spoke wheels but some of the spokes are starting to rust. I just ordered a Delkevic SS exhaust to replace my old V&H 4-1. It was in too bad a shape to have coated and am tired of painting it, so the spokes will have to wait. The last time I checked they wanted more than the exhaust for SS spokes and threading the wheels.

[oldtimer]

Beautiful bike! Is that a stock paint scheme?

Thanks. the paint scheme is my own. After going over a million colors in my mind, I decided to just go with my old high school colors. The maroon and white is paint. the black accent stripes is tape. It was model airplane tape that was supposed to turn to paint in the sun shine. Well it never turned to paint, but it also has never has lofted or come off in 20 years. The front fender was chrome I had ir chemically stripped and painted it to match. I'm not real hip on a lot of chrome and go out of my way to get rid of all I can.. If I wanted to shine it all day, I'd buy an HD