Spark Problem/Timing

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Posts: 32
Joined: Sat Aug 21, 2004 9:52 pm
Location: Massachusetts

Spark Problem/Timing


Post by bonham3 » Sun Aug 21, 2005 4:24 pm

Hi! All

This has been going on for ever and cannot seem to get an answer.
I get spark at both plugs simultaneousley when ignition key is turned to the off position. The bike will start and run O.K. but i get a powerful kickback on the pedal at times when starting. Have already had a bad ankle injury from this. 48 61", mallory elec. dist., dynacoil, accel wires,
harley 3-4 plugs.
Also, weird dist. timing issue. Not sure about position of dist. Lined up
the timing mark on flywheel perfectly centered in view, vertical line with two dots on it with an F next to line. front piston at tdc. both valves closed.
Bike would start but run real rough. rotated dist. one tooth (clockwise)
and bike runs good. How is this??? I have an S&S flywheel. Also has another timing mark for the rear cylinder. Should i use that one?
Could this be part of the spark problem?

Thank's for any help Ron Bonham3

Posts: 369
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Post by kell » Sun Aug 21, 2005 11:29 pm

Are you static timing it (meaning with the engine not running) or are you "dynamic" timing it with a timing light and the engine running?
If you are using static timing you have to turn the timing plate in the mallory to the full advance position and jam it there with a bit of folded cardboard or something, then do the timing. To do dynamic timing with a timing light, you have to rev it up until the mallory timing plate rotates into full timing position -- at least 2000 rpm. Then look in the timing hole with the light flashing and rotate the mallory until you see the timing mark.

I don't know what kind of marks the S&S flywheel has. They are different from the stock flywheel marks. Find out for sure which mark shows TDC and which mark is the timing mark. You have to use the timing mark to set your timing.

Since you said you already have it running, the easiest thing might be to just start it up and shoot a timing light at the hole. If you don't see a mark in the hole, rotate the mallory a bit either way until you do. Remember you have to rev it up.


S&S wheels..


Post by Guest » Mon Aug 22, 2005 1:54 am

The timing marks on the S&S wheels in my pan (a set put in about 13 years ago, 4 1/2 stroke) show, as they come up when you rotate your kicker, first a " . R", next a " l F " (your timing mark), then a few degrees later a " T : F ", which is TDC for front. If you are timing it off a " : F " mark, I'm sure it kicks back as your timing is too advanced. Maybe your wheels use just a " l " as the timing mark.

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Location: Massachusetts



Post by bonham3 » Mon Aug 22, 2005 1:38 pm


I'll try rotating the dist. one notch and see what happens.
The pedal kickback usually only happens if i slightly flood it.
Now if i can get that spark problem fixed. Can't figure it.
Always was that way. Big mystery.

Posts: 80
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Bikes: 1955 FL on a 54 frame
2012 Heritage Softail Classic
Location: Inola, Oklahoma


Post by Red55FL » Mon Aug 22, 2005 3:14 pm

Kell is right; you have to make sure that the timing plate is fully advanced when setting the timing.
You will never get it properly timed by rotating the breaker shaft a few teeth and trying it. Your ankle might get hurt again.
Here is an easy way to static time it & how I got my breaker timed right.

1. Pull the top off of the Mallory breaker, the spark plugs and the timing plug.
2. Hold a finger over the front cylinder spark plug hole while you turn the engine over slowly until you feel the piston come up on the compression stroke. You will feel pressure from the spark plug hole.
3. Continue to slowly rotate the engine until the timing mark on the flywheel is just coming into view in the timing hole. Pay attention to the direction that the shutter is turning so you will know if the shutter window is moving toward the photocell or away from it.
4. With the breaker in the full advance position, the shutter window should just be starting to line up with the photocell.
5. If the breaker housing can be rotated to the point that the shutter widow is just starting to line up with the photocell, then put the plugs on the plug wires, but don't screw them into the heads. Put the top back on the Mallory breaker, ground the plugs threads and turn on the switch.
6. Slowly turn the breaker housing in the opposite direction that the shutter was turning to the point that the plugs fire. You may have to rock it back and forth several times to get it close.
7. Lock down the breaker housing hold down bolt. This will get the timing close enough to start the engine and time it with strobe timing tight.
8. If the breaker housing can't be rotated enough to get the shutter window to just start to line up with the photocell, you will have to pull the breaker housing out of the engine and rotate the shaft a few teeth one way or the other. Then do steps 5, 6 & 7.

After I timed mine this way, it was dead on when I checked it with the strobe light.

The reason that the coil fires when you turn off the switch is that with the switch on, power is flowing through the coil primary windings. When the switch is turned off it has the same effect as opening a set of points, the electrical field breaks down causing a power surge in the coil secondary windings and a spark. This is normal & nothing to worry about.


Posts: 32
Joined: Sat Aug 21, 2004 9:52 pm
Location: Massachusetts

A Miracle :)


Post by bonham3 » Mon Aug 22, 2005 5:55 pm

First off, thank's to all that helped.
And to "Red" for his informative and patient note.
I static timed it and for the first time the
bike started on the first kick (Cold) Not bad for a 48.
Goes to show that being off just a few degrees can
make the diff.
Also, My plugs do not fire anymore when i turned off the key.
Just a thought, maybe this is another way of static timing
if you had the same problem. Red stated it was normal but maybe
not for a Dynacoil or elec. ignition module. The pedal did not kick back also.
F.Y.I for future posts, I dropped the dist. in with the F l timing mark.
This is for S&S wheels anyway. The arrows line up with the R l mark
but this is off. The T:F (TDC) mark is one tooth off if dist. is dropped in.
Wait a min. I think i have an STD wheel (Oh well) anyway, it worked.
Dynacoil note: If you use one and did not know, I wrote the manufacturer
and they said it does not matter which terminals you hook up your wires to. I.E.: Pos./Neg. They do not exist on this coil.

One last stupid question: In case i want to retard the timing just a tad,
do i go C or CC with dist. housing? (I am looking down at it from the right side of bike).

Once again Thank's to all. Now back to that tranny sprocket drip :)
Well, maybe over the winter :)

Ron , Bonham3, Massachusetts (I'm right on the N.H. border, though, Thank God :)



Post by RussW » Tue Aug 23, 2005 4:16 am

retard by turning breaker clockwise. That should also prevent kickback when starting. Near N.H. border, huh? I'm near Springfield.

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