FYI, carbs mixture screws, 1980 GS550E

[cmn1771]

my bike had been holding high rpms after letting off of throttle. it was slow to return to idle. i heard that this may mean a lean condition. so i pulled the spark plugs i noticed they looked like the bike had been running lean. i checked the mixture screws on the carbs and they were all nearly on 2.5 turns out. i read here on a carb thread that this model should be closer to 3.5 turns out. so iv set them all to 3.5 turns out and adjusted idle accordingly. i did a short test ride and it seems fine. ill do some more test rides soon and report back. hope this helps others with a 1980 gs550.

-matt

[Nessism]

Have you replace the intake pipe O-rings yet too?

[BassCliff]

Hi,

In your "mega-welcome" is a list of maintenance items that need to be fixed, checked, adjusted, cleaned, replaced, etc. Completing these tasks will ensure proper operation, or at least establish a solid baseline for further troubleshooting and adjustments.

To ensure your "idle mixture adjustment" screws are properly set, use the "highest idle" method. Listen to your engine and it will tell you where they should be set.


Thank you for your indulgence,

BassCliff

[cmn1771]

Have you replace the intake pipe O-rings yet too?

no, they look like new

[Nessism]

no, they look like new

The O-rings look like new? Did you remove the intake pipes to look?

[BassCliff]

Have you replace the intake pipe O-rings yet too?

Hi,

This is what Mr. Nessism is talking about, the O-rings between the head and the intake boots. Notice the damage.



Here's one that I replaced recently.



Mine were flat as a pancake and probably leaking all over the place. I replaced with new O-rings, no leaks.



To see the entire air intake repair process, have a look at this guide (PDF file):

Air Intake Repair:
Airbox removal, intake boots and O-ring replacement

Thank you for your indulgence,

BassCliff

[cmn1771]

yes and the boots look great too.

today i did a few more tests rides and im happy with the results. the spark plugs really tell a story. first all were too lean. then after adjusting carbs they were all good except #3. it was still too lean so i richened it up and thats where im keeping it. all the spark plugs are now the correct coloring.

and it runs and idles great! im stoked about this bike! wooohooo

im gonna do the valve clearance check as soon as the tappet tool comes in. maybe they will need no adjustment, but if they do, ill have to order some shims. where do u guys recommend getting them?

thanks
matt

[Steve]

Just to make sure we are all on the same page ... which one are you calling #3?

Please remember that #1 is under your clutch hand, #4 is under your throttle hand.

.

[BassCliff]

im gonna do the valve clearance check as soon as the tappet tool comes in. maybe they will need no adjustment, but if they do, ill have to order some shims. where do u guys recommend getting them?

Hi,

There are a couple of options here. You can join the Shim Club and trade for the shims you need. Or you can perform your valve checks, inventory your shim sizes, and order what you need from Z1Enterprises.com for about $5 each.

I use Mr. Steve's handy-dandy spread sheet to track my clearances and installed shim sizes. Then I can order ahead any shims I may need for future adjustments.

From my website, for your reference (PDF file):

Valve Adjustments (8 Valve)


Thank you for your indulgence,

BassCliff

[cmn1771]

Just to make sure we are all on the same page ... which one are you calling #3?

Please remember that #1 is under your clutch hand, #4 is under your throttle hand.

.

yes, correct