Screamin Eagle Keihin butterfly carb. Anyone one know anything about them?
Seasoned HDF Member
Joined: Jul 2014
Posts: 8,569
Likes: 3,324
From: Cental, MI
At least it is American [the S&S] so good on that
Now lets really stir the ****, and throw in the new Mikuni while we're at it.
Wondering who will be the first to tell us what mikuni America means!!!!
Luckily I can make an old Ka-sneeze work or certainly a Bendix [American Made also] so I'll just say that I stand by My Favorites..But Don't throw the S&S away...I have had some extremely good Luck with S&S on the Drag Strip!!!!!
Now lets really stir the ****, and throw in the new Mikuni while we're at it.
Wondering who will be the first to tell us what mikuni America means!!!!
Luckily I can make an old Ka-sneeze work or certainly a Bendix [American Made also] so I'll just say that I stand by My Favorites..But Don't throw the S&S away...I have had some extremely good Luck with S&S on the Drag Strip!!!!!
Novice
Joined: Apr 2017
Posts: 15
Likes: 0
From: Naples Italy
I have to say that I have found this thread very useful since this week I looked past the air filter on my recently purchased '89 FLHS and found a Screamin' Eagle Keihin non CV carb. My bike also had what I believe to be the original H-D spark plugs still in it. It had only done 12000 miles and they were starting to break down after 28 years (!) and affect the running of the bike so I pulled them and replaced them with a pair of NGK BPR5ES-11 set at 0.9mm gap. This sorted the ignition issues I was having but after a run out I pulled them again and the the bad black colour that the originals had continues to indicate rich running. So the question is how to adjust this rich running. I should say that I have not yet inspected the air filter so if it is old/minging that might be the culprit but I would welcome any advice. I have a service manual but it is not helpful...Can anyone help?
Seasoned HDF Member
Joined: Aug 2007
Posts: 8,196
Likes: 3,085
From: NW AR
If I recall, there is a standard low speed idle adjustment screw on top, and the main jet inside can be swapped out.
Start with a new air cleaner and I'd replace the compliance fittings before I went any further messing with the carb.
Start with a new air cleaner and I'd replace the compliance fittings before I went any further messing with the carb.
Novice
Joined: Apr 2017
Posts: 15
Likes: 0
From: Naples Italy
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Seasoned HDF Member
Joined: Aug 2007
Posts: 8,196
Likes: 3,085
From: NW AR
I just happen to have the original MoCo Instructions for that carb sitting in front of me. Part number 91731-85A. Lessee:
Operation and Adjustment
Idle Mixture - The idle mixture screw is initially set at 5/8 turn outward from the full in position. Do not set idle speed or smoothness with this screw, it must be set within 1/8 turn of the 5/8 position. this screw adjustment has a great effect on the entire fuel curve.
It came with a 140 and 150 main jet. The part number for a 130 is 27106-85. Anyway, if you need other part numbers, I have them for the main, slow and power jets.
Operation and Adjustment
Idle Mixture - The idle mixture screw is initially set at 5/8 turn outward from the full in position. Do not set idle speed or smoothness with this screw, it must be set within 1/8 turn of the 5/8 position. this screw adjustment has a great effect on the entire fuel curve.
It came with a 140 and 150 main jet. The part number for a 130 is 27106-85. Anyway, if you need other part numbers, I have them for the main, slow and power jets.
Novice
Joined: Apr 2017
Posts: 15
Likes: 0
From: Naples Italy
Thanks for this - I am now having trouble sourcing a replacement air filter for this - the type that fits straight on the throat of the carb using just one Jubilee Clamp. Anyone got a part number for this mushroom shaped K&N Cleaner?