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Hopefully, this info will help others and shorten the process if you have a similar combination.
I have a 79 XS11 SF that has 1980 XS11 SG carbs on it. The jetting for this carb is radically different from the 79 carbs. The 79 carbs had suffered a fire in one of them, had broken float post in another, and corrosion welded in parts in the others, and I couldn't locate some parts for these carbs, so I found the 80 SG set through a salvage company in Florida. Since I put on these carbs, I have suffered from a off idle stumble for a long time now and finally decided to fix it.
After many, many combinations (read 25 times of pulling, cleaning and changing combos of jets, float height, needle height, etc), I have finally arrived at the following combination that works well. The plugs are tan, the bike pulls hard from idle all the way up and is just plain scary now.
Stock bike, stock exhaust, EMGO cone filters.
Main jet 132.5 - all four (way bigger than stock 80 SG)
Pilot jet 42.5 (back to stock after much experimentation)
Main air 140 (back to stock ")
Float height 23mm off gasket on all four
Needle jet Stock size, don't know it.
Needle Stock size, don't know it. Milled down the plastic doughnut by .050 on each one. Much experimentation here.
Hope this saves someone some time!
I have a 79 XS11 SF that has 1980 XS11 SG carbs on it. The jetting for this carb is radically different from the 79 carbs. The 79 carbs had suffered a fire in one of them, had broken float post in another, and corrosion welded in parts in the others, and I couldn't locate some parts for these carbs, so I found the 80 SG set through a salvage company in Florida. Since I put on these carbs, I have suffered from a off idle stumble for a long time now and finally decided to fix it.
After many, many combinations (read 25 times of pulling, cleaning and changing combos of jets, float height, needle height, etc), I have finally arrived at the following combination that works well. The plugs are tan, the bike pulls hard from idle all the way up and is just plain scary now.
Stock bike, stock exhaust, EMGO cone filters.
Main jet 132.5 - all four (way bigger than stock 80 SG)
Pilot jet 42.5 (back to stock after much experimentation)
Main air 140 (back to stock ")
Float height 23mm off gasket on all four
Needle jet Stock size, don't know it.
Needle Stock size, don't know it. Milled down the plastic doughnut by .050 on each one. Much experimentation here.
Hope this saves someone some time!
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