Dyna S ignition timing

[Guest]

Hey guys, I've read all the DIYs and checked my service manual and I can't seem to get the same straight answer for exactly how to set the timing for the Dyna S ignition. Here's what I have right now. On BikeCliff's website I used the Install Dyna S Ignition link to set the static timing. I just can't figure out which tick mark to use. Here's what is mentioned in that PDF:


"Turn the engine clockwise until the rightmost mark (full advance) for 1-4 is at mark.Turn the advancer fully by hand.You would expect the light to go on, exactly when the advancer is fully turned.If not loosen the base plate and turn is slightly in the elongated holes."

So if I'm reading this right, I need to time the ignition statically by setting the mark to the rightmost "full advance" tick. When this happens, I should get my test light to light up when I have it connected to the white wire and ground.


However, I seem to be getting a different answer on bwringer's site:


He is saying I need to line up the mark to the T tick, which is the leftmost tick. This is quite a difference, and my manual doesn't provide much help since the old ignition was non-adjustable.

Can someone please explain to me which tick I need to line up with the mark in order to get the timing set correctly? This is a static timing of course, since I don't have a timing light. I also need to figure out how to do plugs 2-3, since there is only one tick that I can see, then the number "470" to the right of that. I can provide pictures if need be.

[8ball]

The "T" is top dead center. You don't use that for spark ignition timing. You set the ignition unit to the ignition timing marks. The instructions have you manually advance the advancer as you turn the crank. This is slightly difficult, but doable.....it'd be easier if we had three hands. Once you have the firing pair set, you will notice that the light will light up at the "F" mark, when you don't have the advancer twisted to full advance. Funny how that works.

As as far as 2-3, there should be timing marks for that pair, as well. I find it strange yours doesn't

[posplayr]

Static timing means only one thing. The bike is not running and so the mechanical advance is zero, the coil fires at the initial timing mark. On the GS the initial timing mark is the F.

If you do dynamic timing say with a timing light, the light will blink when the coil fires and you will see the mark move. When set properly it moves from "F" at idle to the full mechanical advance mark at 2500 RPM and above.

TDC is useful in certain circumstances like when degreeing cams (as a secondary check), but is generally not needed for ignition timing.

[TylerM]

So you're saying my goal is to have the test light light up when I'm on the F mark? Here's some pictures of my ignition. I took the plate off so you can see things a little better.

1&4, looks normal


2&3, what's going on here? Where should the light be turning on at?

[TylerM]

Static timing means only one thing. The bike is not running and so the mechanical advance is zero, the coil fires at the initial timing mark. On the GS the initial timing mark is the F.

If you do dynamic timing say with a timing light, the light will blink when the coil fires and you will see the mark move. When set properly it moves from "F" at idle to the full mechanical advance mark at 2500 RPM and above.

TDC is useful in certain circumstances like when degreeing cams (as a secondary check), but is generally not needed for ignition timing.

Thank you. That's exactly what I was trying to figure out. Now the question is what do I do for 2&3 since I don't have an F mark? I posted a photo for reference.

[8ball]

What he said^^^

But just so you know, posplayr, the Dyna S installation instructions have you set the timing at full advance, and to do this, you have to turn the crank till it lines up with the right most (full advance) mark, hook the test light up, and twist the advancer to the right. The light should come on when the advancer hits the stop. And like I said, if you test it with the light without twisting the advancer, the light will light up at the "F" mark..

[TylerM]

What he said^^^

But just so you know, posplayr, the Dyna S installation instructions have you set the timing at full advance, and to do this, you have to turn the crank till it lines up with the right most (full advance) mark, hook the test light up, and twist the advancer to the right. The light should come on when the advancer hits the stop. And like I said, if you test it with the light without twisting the advancer, the light will light up at the "F" mark..

That's what was confusing me initially, because the Dyna S instructions weren't making sense. What exactly do you mean when you say the advancer hits the stop?

[TylerM]

Ok here's what's currently happening. The light comes on about halfway between the full advance mark and the F mark. As I continue to turn clockwise the light stays on until I get just past the T mark.

I'm assuming what the Dyna S instructions meant was that the light needs to be on from the beginning of the full advance mark to the F mark. Is this correct?

[gs rider]

you turn the advancer, black round piece with magnet in it all the away around to right - till it stops (about a 1/4 turn) while also slowly spinning the crank with the 19 mm wrench. slippery devel. This pushes the black plates with springs attached on your advance face out- guess it simulates high speed-rpm riding, while we find the allusive advance f mark. Easily marked on one side on mine(the right) just opposite of your pics. not so on left. The one above the 4 on your left side pic is one you want i believe. Set that first to light on and aligned with casing mark via moving the dyna plate then you/we adjust right side just to light by moving the dyna trigger via little allen heads.

[8ball]

The black piece that the yellow arrow is pointing at twists on the shaft. It springs to the left stop, and advances to the right with centrifugal force. The instructions tell you to twist it to the right. That is the full advance position. You turn the crank to almost line up with the right most mark, and then twist the black piece on the advancer to the right, and hod it against the stop as you turn the crank to line up with the mark.


Now as to why your assembly is missing the 2-3 marks. You original ignition was electronic, and had no adjustment individually for the 1-4 and 2-3 pickups. They were set 180 degrees apart. You will probably need a degree wheel to find where the marks should be....... Which brings me to the question: Since your bike had no breaker points, why exactly, are you installing a DynaS?

[OldVet66]

If you mark your points plate slot location on the nearest casting with a sharpie and mount your Dyna plate as near as you can judge it, the bike will most likely start and run. Then time it with a light on 1-4. You will most likely have to slip the 2-3 sensor to get the same timing marks to line up to the appropriate marks. They are real close from the factory but not always perfect. Then you can forget about it, it's timed properly and you will know if the advance is working properly.

[posplayr]

What he said^^^

But just so you know, posplayr, the Dyna S installation instructions have you set the timing at full advance, and to do this, you have to turn the crank till it lines up with the right most (full advance) mark, hook the test light up, and twist the advancer to the right. The light should come on when the advancer hits the stop. And like I said, if you test it with the light without twisting the advancer, the light will light up at the "F" mark..

OK I understand now why they would do that. Even if I had read the DynaS instruction I forgot them long ago. So as you say, you can static time either using the "F" mark for idle (no mechanical advance) or the Full advance line assuming full mechanical advance. Since the plug will only fire at the moment you open the ignition circuit, you are simply making sure that this is occurring at either one of these two points.

If you pick F by rotating the engine there, then you need the timing plate so loose that you can slide it around (probably what I did). Alternatively you rotate the engine to the full advance mark and then by hand rotate the advancer to make sure the spark occurs as you high the limit for maximum mechanical advance. The trick is you have to stay just inside of the mark else you might just not get there.

I have a $35 timing light so I can confirm both marks with a running bike and an independent measurement.

[posplayr]

Thank you. That's exactly what I was trying to figure out. Now the question is what do I do for 2&3 since I don't have an F mark? I posted a photo for reference.

I used a timing light.......

[TylerM]

I can't twist that black pickup with my hand unless I loosen the bolt. I have it torqued to spec and it won't twist by hand

[8ball]

That isn't good. It should move freely