Editor’s Note: We are going to work with S&S, Baker,
BDL, Compu-Fire and other Bikernet Sponsors, on their most
asked tech questions. We’ll try to deliver the info you need
access to. The following came from Howard Kelly, the former
editor of HOT BIKE, and now an S&S tech editor.
“We take tech calls all day long here,” Howard said. “Most
people have monkeyed with
their carb so much they lose the baseline. Before we can do
anything else,
we have to get them back to a starting point so they can tune
the carb to
their bike.
These 10 simple steps make tuning an S&S Super E or G a
breeze--on the road
or in the garage.”
1-Verify carburetor is set to stock settings:
A. Idle Mixture Screw, 1 1/4 turns from lightly seated
B. Idle Speed Screw, ½ turn clockwise from engagement
point
C. Accelerator Adjustment Screw, 2 turns counterclockwise
from seated
1. Start bike, bring to operating temperature. Close
enrichener as quickly as possible.
2. Set Idle Speed Adjusting Screw, clockwise to increase
rpm, counter-clockwise to decrease rpm
3. Adjust air/fuel mixture by turning Idle Mixture Screw
slowly clockwise until the engine runs poorly. Slowly turn the
screw counter-clockwise until it runs smoothly—if you go too far
the engine will start to stumble.
4. With engine idling, turn Accelerator Adjustment Screw
clockwise until it lightly seats. Snap throttle open—engine
should stumble. Turn screw counter-clockwise ¼ or ½ of a turn
at a time, until engine responds to throttle twist with smooth,
quick response.
5. Ride motorcycle in various RPM ranges, and then try to
maintain a consistent 40- to 50-mph. If the engine is popping
or sneezing in the air cleaner it can indicate a lean condition. If
you notice stumbling or sputtering it can indicate a rich
condition
6. Replace Intermediate Jet as necessary—smaller is leaner,
larger is richer. Adjust Idle Mixture Screw and Idle Speed Screw
as required.
7.To test the Main Jet, do a high gear roll-on from 50-mph
to 70-mph. If the engine back fires or breaks up in the carb,
increase the Main Jet size .004”. If the engine is flat or will not
accelerate, decrease the Main Jet by .004”.
8. After changing the jets, test ride the motorcycle.
Continue re-jetting and adjustmenting until optimum
performance is achieved.
Note: Drag or straight pipes can prevent you from
obtaining optimum carburetor performance.
Howard Kelly
S&S Cycle Inc.
235 Causeway Blvd.
La Crosse WI 54650
(608) 627-0284
