Installing the dyna s ignition still 2 and 3 plugs not working

[mike_of_bbg]

So your saying run a wire directly from the battery to the coil and also run it the dyna s red wire

That's the idea behind the coil relay mod, which many of us have done to boost our coil voltages.

It's likely multiple issues. If you're not getting any reading between the plug caps even with your multimeter set to 200K ohms or higher, that's an issue. I just checked my 1-4 coil and got 24.5k ohms cap to cap, which is right down the middle with NGK plug caps @ 5k ohms each. You can unscrew the plug caps from the wires and test them independently. Cut 1/4" of the wire to get some fresh copper and test straight copper -> copper without the plug caps, so you should get ~14k.

If your volts are low due to low coil voltage AND you have really bad plug caps you'd be lucky to get any spark at all.

[trucker]

That's the idea behind the coil relay mod, which many of us have done to boost our coil voltages.

It's likely multiple issues. If you're not getting any reading between the plug caps even with your multimeter set to 200K ohms or higher, that's an issue. I just checked my 1-4 coil and got 24.5k ohms cap to cap, which is right down the middle with NGK plug caps @ 5k ohms each. You can unscrew the plug caps from the wires and test them independently. Cut 1/4" of the wire to get some fresh copper and test straight copper -> copper without the plug caps, so you should get ~14k.

If your volts are low due to low coil voltage AND you have really bad plug caps you'd be lucky to get any spark at all.

what do you mean cap to cap I did it with red probe on the orange wire in the black probe in the boot. I thought that is how it was done. so your saying black probe in one boot and the red probe in the other boot

[mike_of_bbg]

To test the coil secondary you set your multitester to an ohmmeter setting above 20k ohms, pull the plug caps of of the plugs, and measure from plug cap to plug cap.

To test the coil primary you measure the wiring harness side between the coil leads at your lowest ohmmeter setting. The reading should be much, much lower: less than 10 ohms (5 or so with stock EI coils IIRC).

[trucker]

I just tried from plug cap to plug cap on 200K on to spare coils and nothing at all no reading

[mike_of_bbg]

I just tried from plug cap to plug cap on 200K on to spare coils and nothing at all no reading

Well, first I'd do it to the ones on the bike. If it's too high to read one or both of the plug caps probably has a burnt resistor on board. Sometimes they'll still fire but it saps some of the energy and you're already dealing with low coil voltage. On the stock coils the conductor is stranded copper in the middle and the plug caps just screw on to the wire, so like I said you can just un-screw them and test the caps independently, and also test wire-to-wire without the caps. Cut 1/4" of wire or so to expose fresh copper. Stock caps should be ~10k ohms each. A stock coil should be ~14k with no caps at all.

I think the resistor in the cap is removable: you can unscrew the contact on the plug end. Some have replaced the resistor with a chunk of brass bar and had success bringing them back to life.

From the electrical odds-n-ends link on BikeCliff's site:

For replacing the stock caps use 2 each - NGK XB05F and VB05F.

Cut off a small slice (1/4 inch) of the end of the plug wire and screw in the new plug caps. This makes a good connection with fresh (uncorroded) wire.

I have those NGKs on my bike also and I think they're good for pretty much all 4-cyl GSes. As noted they're only 5k ohms but that's just fine.

[JTGS850GL]

I put the meter on the black and orange wire with key on and got 8.8 and on the 1 and 4 coil I also got 8.8

There should be an Orange/White wire that goes to the coils. What is the voltage on that wire for both coils.

[trucker]

Well, first I'd do it to the ones on the bike. If it's too high to read one or both of the plug caps probably has a burnt resistor on board. Sometimes they'll still fire but it saps some of the energy and you're already dealing with low coil voltage. On the stock coils the conductor is stranded copper in the middle and the plug caps just screw on to the wire, so like I said you can just un-screw them and test the caps independently, and also test wire-to-wire without the caps. Cut 1/4" of wire or so to expose fresh copper. Stock caps should be ~10k ohms each. A stock coil should be ~14k with no caps at all.

I think the resistor in the cap is removable: you can unscrew the contact on the plug end. Some have replaced the resistor with a chunk of brass bar and had success bringing them back to life.

From the electrical odds-n-ends link on BikeCliff's site:



I have those NGKs on my bike also and I think they're good for pretty much all 4-cyl GSes. As noted they're only 5k ohms but that's just fine.

I i just check the good coil on bike and still no reading on that one to I am at a loss and the resistor what is that are you talking the brass piece inside the boot

[trucker]

There should be an Orange/White wire that goes to the coils. What is the voltage on that wire for both coils.

Orange and white and black to orange are both 8.8 volts

[JTGS850GL]

Those voltages are way to low. What is the battery voltage?

[trucker]

Those voltages are way to low. What is the battery voltage?

The battery was just bought about a week ago and it is like 12.4 I think

[mike_of_bbg]

OK, let me help you out with some pics:

In this one, I have an old OEM plug cap. The DMM is set to 20k Ohms range, and the cap is reading a valid amount of ~9.5k ohms:

[mike_of_bbg]

OK, now, if you look down the plug side of the plug cap, you can see the brass part that grabs the end of the plug. Notice that it has a slot cut in it, almost like you could put a flat-head screwdriver on it:

[mike_of_bbg]

Now, if you actually unscrew that part from the plug cap, it will come out with this little white chunk. That little white chunk is a resistor, which gives it that ~10k Ohms resistance. That's what burns out. When it does burn out, the resistance will go way up and cuts your spark down. If you can cut a little chunk of brass or similar to replace it you can bring that plug cap back to life.

[mike_of_bbg]

And finally, here's my DMM set to 200k Ohms. The red lead is stuck in my plug cap for #1, and the black in the plug cap for #4. You can see it reads ~24.5k Ohms. That's ~14k for the coil itself, plus 5k each for the NGK plug caps.

[mike_of_bbg]

I hope those pictures could convey what words could not.

You should measure your battery voltage. New or not, cranking will - and idling can - drain it. Closer to 13 is what you want to see. What you also want to see is <1V drop from battery voltage to coil voltage (at the orange/white wire on each coil). If you're not seeing that then you need to start cleaning connections, and also consider a coil relay mod. Don't skip the connection cleaning, but your voltage drop is frequently from the ignition or kill switches which are a real bear to disassemble, clean, and get back together right.

However, in addition to the low voltage, if you swapped the coil leads and the spark (or lack of spark) followed the coil and not the leads you swapped, then I'd suggest that you have a coil that's not up to snuff. The plug cap issues are common and easy/cheap to fix. These GSes can be pretty forgiving of single issues, but when you get multiple issues going that's when things go south fast. Get it all fixed while you're in there and you can prevent some self-tail-chasing in the future.