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Discussion Starter #1 (Edited)
I had my bike (95 SS) into the dealer at the end of the riding season last fall for valves/belts. Despite me asking them not to touch anything else they politely "adjusted CO levels". After I got it back I only ran it enough to work some Sta-bil through the system.

This spring I got the bike out, and it seems to be running lean. The low end is jumpy, like there's no clutch feel, it rev's down slowly, and heats up (judging by heat coming off, don't have a temp gauge on it). All of which seem to point to a lean mixture. I drained the bowls, and put in new gas, and it still does it.

My question is: when a dealer "adjusts CO levels" what do they normally mess with? Do they lean out the overall mixture?

EDIT: I backed the idle mixture out 1/4 turn and it evened out the low end, but it still revs down slow. Any other ideas?
Thanks
 

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When you say revs down slow, do you mean the idle comes down slow? If thats the case then its generally a sync issue or a small vacuum leak causing the carbs to see unmetered air.

Did the dealer say why the adjusted the mixture screws? Unless theres an issue I dont see why they would have.
 

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Discussion Starter #3
Yes, it idles down slow. I'm gonna call the dealer tomorrow and see what they usually change for this adjustment. I hate to think what syncin the carbs is gonna cost me, especially since the Haynes manual says they use some special machine that only dealers have.

Any other suggestions? I guess I'll keep fiddling with it and see what happens...
 

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CO levels

Was the sta-bil run through the bike? If not perhaps there was some gumming of the slides. Check the manifolds/bleed orifices (if fitted) on the manifold tubes for tightness. Check for gummy cables/throttle - should snap back. Is choke sticking (if fitted)? All they really need at the shop is a manometer (liquid filled tubes) to measure vacuum to synch the carbs. To adjust Idle CO they'd use (or should have used) a CO meter hooked up to tubes attached to each header, then adjusted ONLY the idle air inlet (pilot). I could be off on my terminology - just going from memory (now have a 900SSie - no longer have old SS, and currently have a off road thumper carb bike, where I simply adjust Idle with the pilot screw at bottom of carb)
 

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Discussion Starter #5
yes the sta-bil was run through the bike. I checked choke, throttle snap, etc. I now have the main fuel screw (under the bowl) backed out 6 turns each. I'll run it a little and see if that helps. It still hasn't smelled too rich so maybe it was more lean than I thought. It idles down eventually so I dont think its a vaccum problem. Next will be syncing the carbs I guess.
 

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Discussion Starter #6
Just wanted to update this in case anyone runs a search and has the same problem.

Turns out the issue had nothing to do with the carbs/or CO mixture. The green/black wire running from the starter button and kill switch was almost completely severed! There were a few strands barely attached, which is why it would intermittently shut off. I'm not completely positive how this made the rev's come down slow, but after replacing the wire it has stopped. Only thing I can figure is there wasn't enough current passing through the wire, maybe hurting the whole electrical system?

Anyhow, thanks for the help everyone.
 

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damn electrical gremlins.

how did you discover the bad wire? [what led you to dis-assemble the switch gear]

btw, to sync the carbs you need nothing more than a $20 set of mercury tubes. [carb sticks is the term you'll hear most often, they are vaccum gauges]
 

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Discussion Starter #8
Funny how I found the wire, I was backing up in the driveway and swung the bars from one side to the other and it shut off. My dad and I started shaking wires connected to the handlebars, and sure enough everytime the one was shaken it shut off.

Turns out my dad has those gauges to synch the carbs, I've never had to do it so I never knew.
 
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