Ed Moore says:
This is the way I
tune my engines after much listening to others and reading of other folks information. I'm
not Mr. Honda the engine designer. Just a feller with information I have gathered and wish
to pass on to those that can use it. .........emo
PS This process
figures you will start at the beginning. As though you just reassembled the engine.
"Read and understand process before you start". Makes process easier!!!!!!
Are you looking for a way to
perform the ultimate tune-up on your CB72/77, CP77 SuperHawk or CL72/77 Scrambler Type
I (180º, dual points) motors? Ed Moore - always more
than generous with help and good advice - has devised a special set of instructions to
produce a better tuned motor. On behalf of everyone who will have a better running
machine, many thanks, EMO!!!
- .014 feeler gauge (to set right
- Spark plug wrench
- Large vise grip pliers (to put on
the bolt head at the rotor so engine crank will be able to be moved back and forth) The
crank will go "OVER CENTER" if you use wrenches!!!!!!!!
- Phillips screwdriver (plate and
- Flat head screwdriver (points
- 12 volt light with one foot long
wires and alligator clips on the end (to see exactly when the points open) NOT A TIMING
- Remove point and rotor covers.
Clean both sets of points. MAKE SURE THEY ARE CLEAN!!!!!!!!!!!!
- Install new spark plugs.
- Turn carb slide adjuster screws out
enough for the slides to bottom out on the carb.
- Adjust air screws to 1 1/8 open
from bottom. Will readjust when engine is hot!!!!!
- CB72/77 - Remove the air
intake tubes and put middle finger in left carb and thumb in the right carb.
CL72/77 - Remove the tool can and put middle finger in left carb and thumb in the
- Move throttle handle and if both
slides don't move at "exactly the same time" adjust the screws on the top of the
carbs so they do. Be sure to have at least 1/8 inch slack in the throttle handle.
- Set "R" points to .014.
Tighten the screws. (you are through with them!
- Put alligator clips on the
"R" points and engine case. Put bulb behind the left carb. BRIGHT YOU KNOW!
- Turn key to "ON".
- Turn crank with Vise Grips so
"F" is in line with pointer at rotor area. (The mark on point cam should be
down. If it is up. Crank engine 360 degrees.)
- Loosen points plate.
- Hold crank somehow at "F"
to marker and adjust PLATE so light JUST comes on at "F".
- Tighten plate. Check opening now by
moving pliers forward then back. If light comes on other than at "F". Adjust
plate until it does when the plate is tightened. May require a couple of adjustments. You
are through with the plate.
- Move alligator clip to
- Move crank 180 degrees.
- Loosen "L" points and
adjust until light just comes on at "LF".
- Tighten and check by moving crank
back and forth. Readjust if needed.
When both points are adjusted:
- Turn off key switch.
- Remove tools and turn slide screws
in a couple of turns.
- Choke lever to 3/4 closed.
- Turn gas lever on. WAIT!
- Engine in "NEUTRAL"
- Key "ON".
- CB72/77 - Push starter
CL72/77 - Kick start the motor.
- Engine will fire and run somewhat.
- Run until you can OPEN the choke
all the way.
- Adjust slide screws to even
- When engine is hot adjust slide
screws so engine idles at around 800 RPM.
- Adjust air screws.
1 1/4 turn max
here. Usually open a small amount to smooth idle. Never more than 1 1/2 turns open from
bottom total. May need to open slide screws after this to lower RPM.
- Install the air tubes and go ride.
If the points are new. You will
find they WEAR IN to the point cam and will need to be adjusted a couple of times until
they are WORN IN.
Seems like a lot but not really because it works.