ok, so heres the issue.....

[kawazuki]

my 1980 gs850g has a stock airbox with stock style filter. also has a v&h 4 into 1 pipe with baffle....just bought the bike and the previous owner claims that the bike was jetted for the pipe. anyways when i am cruising any mph but somewhere in the 4-5k rpm range the bike seems to stutter and sound like poop. i am led to belive this is an electrical isssue because of the fact that it happens 75-80% of the time but not always. if i twist the throttle useally it will pull through it. the bike runs great any other time. any ideas...stuck between advance?....coil...????

[bonanzadave]

Classic air / fuel mix issue. Might be running a little rich. Long story short the carbs gotta be gone through. How do the plugs look. Just for fun crack the airbox lid a bit and see what that does...

[BassCliff]

Hi,

I would wager that the previous owner put in larger main jets but did nothing to the midrange. You'll probably have to shim the needles to richen up the midrange. You'll probably have to set the idle mixture screws to about 2.5 to 3 turns out (use the "highest idle method"). Plug chops will tell you exactly what's going on. Then adjust accordingly. Until you read the plugs, we're just guessing.

There is no "lid" on the 850 airbox. If you have the stock setup, just make sure it's air tight. Then adjust the carbs as necessary. Perhaps a Dynojet kit? (The Dynojet Stage 3 kit comes with three different sets of mains.) Or rapidray will sell you the special tapered and notched needles that will allow you more fine tuning control over the midrange. Just the needles are about half the price of a full jet kit, which is probably overkill for your application.

CLICK HERE for the V&H recommendations. I guess it's a good place to start.

What main jets are installed? I'd try the cheap route first. Do some plug chops right where it stumbles and read the plugs. See if it's rich or lean. Adjust accordingly. Shim the needles (to raise them) if it's too lean in the midrange. This is what I would suspect first.

Check the carb sections of my website for more information.


Thank you for your indulgence,

BassCliff

[kawazuki]

thanx guys