I am at a loss on what to do next

[scottsgs]

Hi all,

Ok here's the deal. I was originally thinking that the problem my 81 GS850G has was fuel related. I went through the carbs and made sure float height was in spec, no holes or tears in the diaphrams, and that their general condition was clean. The next thing was the petcock. I found gas in the vacuum tube. I went ahead and eliminated the vacuum according to posts from this site. I now have RES ON and OFF(which was PRI). I have adjusted the valves and syncd the carbs 3 separate times ( adult ADHD). However the bikes starts to break down like it's running out of gas when the throttle is open 1/8 or less. It's most noticeable at 50 - 55 mph. The bike starts fine, idles good, and when the throttle is opened past the 1/8 mark it stumbles for a second then pulls like a freight train. I have been playing with the mixture screws to find out where it runs better. Right now they are set at 2-3/4 turns out. The bike also has new plugs, UNI foam air filter, and new air box gaskets, boots, and intake o-rings. the last thing I have done is repacked my V&H 4-1 can with #3 steel wool.

I am now starting to look at electrical, mostly igniter box and signal generator. I am going to give my ohm meter a work out. Does anyone have any suggestions? I really need help here.

Thanks
Scott

[scottsgs]

Forgot to mention I tested the signal generator las night. Clymer says it should be 290-360 ohms. Mine was 370. should I replace it??

[RJ]

You may want to try shimming the needles so that they are riding a little higher in the piston. Sounds like you may be running lean for a split second until the carbs can catch up.

[Suzuki mad]

Have you checked the ignition timing?

Suzuki mad

[bwringer]

You may want to try shimming the needles so that they are riding a little higher in the piston. Sounds like you may be running lean for a split second until the carbs can catch up.

Yeah, it also sounds to me like it hasn't been rejetted properly for the V&H pipe.

Shimming the needles is a step in the right direction. Are there any other jetting changes in the carbs? Stock is #115 mains, #40 pilots.

I think, maybe, possibly, that with the stock airbox and a pipe, you'll need to shim the needles a bit and go to 42.5 pilots.

That's a logical starting point, anyway.

[Nessism]

How did you eliminate the vacuum line on the petcock? Did you modify the petcock internally in some way?

[scottsgs]

I filled in the moon shaped area.

[tkent02]

Did you DIP the carbs?

[snowbeard]

oops edit, reread and I was not even close ;-)

[chef1366]

There are small ports that connect the main air jet to the main jet and the pilot air jet to the pilot jet. If these do not get cleaned right you'll be chasing your tail.

[lucabond]

Any sharp bend or kink or other then a downward direction of your fuel line from the tank to the carb ?

[scottsgs]

update on At a Loss

Hi all,

Well I shimmed the needles and it was just what it needed! Thanks to all who gave their insight.

Scott