Testing Dyna S

[Guest]

I have been having trouble with my bike stalling once it gets warm. I eliminated all the air and fuel potential issues and decided to install new dynatek coils thinking one was dropping out from heat. It looks like the original coils were still in the bike.

After installing the new coils, cables and sparkplugs I was still dropping cylinder 1 and 4. In order to make sure I just didnt receive a defective coil set I switched the coils. The coil that powered 2,3 was known to work. After switching the coils I still have 1 and 4 dropping out. I tested it with a spark tester and no spark at 1 and 4.

It starts fine with a fine explosion to life and runs well but once warm it drops those 2 with no spark.

Yesterday I bought and installed a new battery.I checked the battery voltage with the ignition switch off and I get 12.66. With the ignition switch on I get 12.16 ish. I disconnected the primary wires from the coil that drops out and checked there and I get 11.43 +/- at the primary wires. Less than a 1 volt drop.

Soooooo I opened the ignition cover and there is a dyna s installed. Here is where I am stuck. I dont know what the two black bits are or how to test to see if it is the ignition that is causing the dropped cylinders. I am imagining that the two black bits are the signal generators. The screw on the rear one was falling out and the unit was allowed to pivot on the top screw. I refastened and took it out but 3 miles later and I was limping home on 2 cylinders. Youtube has been pretty good to me but nothing on how to test to see if the dyna s is the culprit.

I know these are pretty popular so I am hoping someone can lead me to how to test the dyna ignition. I dont want to just keep replacing things but I have to imagine that this is the final step ?? I hope!?
Below are pix of what I see when I open the ignition. I have a meter and a cursory knowledge on how to use it. Any help would be greatly appreciated.

http://boriqualeather.com/stuff/GS750/dyna%20s1.JPG

http://boriqualeather.com/stuff/GS750/dyna%20s2.JPG

Quick run down on what has been done
Tank cleaned and lined
New gas cap
New fuel and vacuum line
New Petcock
Cleaned and rebuilt carbs
New oiled airfiliter
Air leak check with starter fluid
New dynatek coils, wires and caps
New plugs
Fresh oil and oil filter
new battery
Running premium 91 octane gasoline.

[Carter Turk]

I've had 2 Dyna-S's go bad on a 1150, 1-4 trigger at 9 oclock was faulty.
Bike would idle fine, then once on the road under load, 2 cylinders were cutting out.

They're a great company to work with, but you have to send the part to them for inspection and wait for the turn around.

I've had stock ignitors go bad too with intermittent firing, causing me to go the Dyna-S route.
I've also had the magnet in the rotor bulge out, scraping the pickup, dropping 2 cylinders in the process.
The newer Dyna-S is much more compact, with the triggers being lower profile then the one pictured.

[bobgroger]

I've had 2 Dyna-S's go bad on a 1150, 1-4 trigger at 9 oclock was faulty.
Bike would idle fine, then once on the road under load, 2 cylinders were cutting out.

They're a great company to work with, but you have to send the part to them for inspection and wait for the turn around.

I've had stock ignitors go bad too with intermittent firing, causing me to go the Dyna-S route.
I've also had the magnet in the rotor bulge out, scraping the pickup, dropping 2 cylinders in the process.
The newer Dyna-S is much more compact, with the triggers being lower profile then the one pictured.

Switch the trigger wires (bullet connectors from the Dyna, then switch 2-3 plug wires to 1-4 and vice versa. If 1-4 still go out it's not the Dyna

[Boriqua]

Switch the trigger wires (bullet connectors from the Dyna, then switch 2-3 plug wires to 1-4 and vice versa. If 1-4 still go out it's not the Dyna

So switch these out?

[bobgroger]

So switch these out?

At the other end of the cable under the right side cover, there are 2 bullet connectors, at least if it was installed per the directions. Simple unplug and swap. It won't start unless you swap plug wires too.

[OldVet66]

I had one Dyna-S failure, have used them reliably for years on different bikes enough to consider them pretty tough. The only failure has been on my GS1000. I installed it before I installed a Series R/R, replaced the stator and cleaned up the electrical system so I believe the electrical problems on my bike contributed to the failure. The voltage drop on your bike is significant. I would suggest maintenance on the electrical system before moving foreword. Your symptoms are consistent with the problems I had except mine was erratic enough to have me chasing my tail a while before it started becoming evident that it was a trigger module failing when it got hot. It was a module failure long after the warranty expired and Dyna treated me fairly for replacement cost.

[Boriqua]

At the other end of the cable under the right side cover, there are 2 bullet connectors, at least if it was installed per the directions. Simple unplug and swap. It won't start unless you swap plug wires too.

I have chased it through and this is what I have. I have a couple of reds that go to one bullet and a white that goes to a blue wire and bullet and then ... a lonely black wire? I am assuming the black is a ground and I am swapping out the reds for the blue and then switching plug wires?

[OldVet66]

Black and white are the trigger wires, reds are power. Both black and white go to a blue wire so mark them before you have to trace blue wires all over the bike. Seems the previous owner didn't care much for color code. None of that is factory wiring.

[Boriqua]

Black and white are the trigger wires, reds are power. Both black and white go to a blue wire so mark them before you have to trace blue wires all over the bike. Seems the previous owner didn't care much for color code. None of that is factory wiring.

Thank you so very much. So I am switching the black and white and switching the spark cables. If it is a trigger that is failing then I should see failure at 2 and 3 now .. correct? If 1 and 4 continue to fail then ... I have to look at something else. You guys are awesome !! Thank you!

The wiring is somewhat of a mess. As with anything this old who knows how many hands have been involved. When I was in my 20's I worked for an electrician as his mechanic in NYC. Very old houses... and ooooooo the things we would find that we would have to decipher when we opened a box!! Scary.

Once I have this running marginally reliable I will probably set about rewiring the bike.
Alex

[OldVet66]

You will probably find most of the wiring in good shape. It's the connectors, plugs, and switches that usually need attention . I would only replace wire that has hard and brittle insulation and that is usually only a few inches from an overheating connection. Make sure you use the proper crimp tools when you get into it, it makes all the difference in the world. There is lots of information on this site on rehabilitating your electrical system. You already eliminated coils as the problem. I'm pretty sure you will find it is a trigger module or the wiring in between.

[Boriqua]

Well Grumble grump grumble .. I am about to tear my hair out and I have really thick hair so its going to hurt! I switched the trigger wires and switched the sparkplug cables like bob suggested and went out. I was riding along kind of confused because I put 12 miles on the bike with nary a hiccup. I was counting on it failing so I could get new clues but it just kept running. Wont idle below 1800 but I figured I could get to that later. I will say I took this ride with the ignition cover off the bike so the dyna was certainly getting the benefit of the wind to cool it but the bike reached about 210 on the gauge and ran fine for longer than it has in the last 10 outings.

Then pulling into my driveway .. fail ... awesome! so I stick my tester on the wires and ... 1 and 4 no spark then it would spark a little and no spark. I expected 2 and 3 to fail with the switching of the wires but its still 1 and 4 with no spark.

I am so damn close!! I can feel it. Any and all advice appreciated fellas.

[60ratrod]

so to test the dyna s, grab a multimeter.
-on the meter, select vdc.
-now put the negative lead to a good ground, the negative terminal on the battery works great for this.
-turn the bike on and turn on the kill switch.
-now meter the orange/white wires, or the 12vdc constant wires and make sure that you are getting close to battery voltage there on both coils.
-if that is good, then move the positive probe from the meter to the signal terminals on the coils individually.
-you should see between .8-1.2 vdc if the pulser coils are good. looking at the dyna unit, the left pulser coil controls 1/4 firing and the right pulser coil controls 2/3 firing.

if you are getting less than .8vdc on either signal terminal, then your unit is bad. I went through this with the first dyna unit I had on my gs650g. I sent it in to dynatek and it tested good with them, but it was still AFU.

[OldVet66]

I would not trust the connections the former owner crimped, those types of connectors are famous for poor connections. You have been moving the wires swapping trigger feeds, maybe literally touching on the problem. What kind of bump is there from the road to your driveway? You are discovering the bike and have no idea what has been done before you got your hands on it. My module failure was so erratically erratic that it drove me nuts for a while until the failures became more consistent . All I have to add at this point is good luck and hope you find it soon.

[Boriqua]

so to test the dyna s, grab a multimeter.
-on the meter, select vdc.
-now put the negative lead to a good ground, the negative terminal on the battery works great for this.
-turn the bike on and turn on the kill switch.
-now meter the orange/white wires, or the 12vdc constant wires and make sure that you are getting close to battery voltage there on both coils.

I am good through here and getting good voltage at the orange and white at the coils
-if that is good, then move the positive probe from the meter to the signal terminals on the coils individually.

Now I am a little lost .. am I measuring at the black boxes at the ignition. Specifically at the trigger wires or at the power wires at the trigger units?

-you should see between .8-1.2 vdc if the pulser coils are good. looking at the dyna unit, the left pulser coil controls 1/4 firing and the right pulser coil controls 2/3 firing.

if you are getting less than .8vdc on either signal terminal, then your unit is bad. I went through this with the first dyna unit I had on my gs650g. I sent it in to dynatek and it tested good with them, but it was still AFU.

[Boriqua]

So I think todays test bears out that it is the trigger for 1 and 4 at the ignition?

Someone check my logic
I had a problem with 1 and 4
I switched the triggers at the bullets but I also switched the spark plug wires which means that I changed 1 and 4 to the right side coil from the left side coil but changed the trigger for 1 and 4 to the right side coil as well.

So if I failed again at 1 and 4 then it is because the left hand (rear) trigger is bad and the test just proved its not the new coils since it happened on both the left and right coil when the trigger for 1 and 4 were attached ... Right?

I had to draw it out on paper to make it make sense but I think I am right ?? maybe

I noticed when I examined the ignition that on the rear trigger the bottom screw was falling out and not held in place and the top was lose. Kinda leading me to believe someone before me was at that trigger as well probably for the same problem.