Ignition Coils

[Tuned forks]

Just pulled my Clymer manual and checked again.  

The spec you cite is listed for the Digital Control Ignition for the 1989 and newer bikes, while the TCI spec is listed at 108-132 ohms.  This is a misprint though huh?  They're both the same resistance value?  

Here's a post from 4 years ago where I went through on my '84 what you just did....(see post #10)
http://www.fjowners.com/index.php?topic=13448.msg135362#msg135362

That was a really good blow by blow thread Pat.  Very useful for someone with ignition problems.

Joe

[AppleJack]

Great - this is good news as I have new plug boots on the way from rpm.  Couple of them missing a small spring ahead of the internal resistor.

And local AutoZone has DPR8EA-9'S in stock per website, shoot they may be 34 years old too  This bike ought to run, only showing 7,800 on odometer!

Thanks to all...

[AppleJack]

So, in my seemingly never-ending search for "the answer" to no-spark condition I found this today. 

Battery voltage of 13.1, but voltage at the connector to the ignition coil (R/W lead) measures 11.5V on the 2-3 coil, and 10.3V on the 1-4 coil.  Also, if I unplug the 2-3 coil connector the voltage on 1-4 comes up to 11.5? 

Is that voltage too low?  R/W lead comes from the "starting circuit cut-out relay"  Where is said relay on the bike?

This same low voltage goes to the IC Ignitor box via a R/W lead also.  Seems too low to me but I'll defer to the experts here on this...

[oldktmdude]

   It's not unusual to have low voltage numbers at the coils. My bike had only 9.5v at the coils but was still starting and running ok. I've done the coil relay mod and voltage is much better. The starting circuit relay that you are referring to, is located under the left hand side of the fairing between the headlight and the fuse box.
This relay is also the indicator unit and is also controlled by the safety switch system ; neutral, clutch and side stand cut out switches.
  Regards, Pete.

[AppleJack]

Wracking my brain here trying to figure this out. 

Here is what's not causing problem: 

Ignition coils primaries and secondaries ohm out correctly and have good dc voltage,

pulse pick-up coils ohm out correctly,

new battery and spark plugs,

kill, side stand, and neutral switches working.

So, I'm wondering if there's a test for the output from the IC Ignitor module? 

Engine cranking what should I see at the grey and orange leads connected to the ignition coils? 

I have 2 of these modules but they are both 34 years old? 

[AppleJack]

So, went out and tried again and I think I see the transistor control must just switch the ground to the coils as the battery volts already there on the R/W lead. 

10.5 volts on R/W lead to TCI - I know it is unrelated but the vacuum diaphragm does hold a vacuum on the suck test

Running out of things to check...

[Pat Conlon]

Let's back up....

The bike was running fine when you parked it...correct?
Now after a period of time, the bike does not want to start.
You think it's electrical because you took out the plugs and laid the plugs on the top fins of the head, thumbed the starter and you don't see a spark on the plugs...

You've checked the ignition coils, pick up coils, side stand switch, neutral switch, 12v power to TCI and you have installed new plug caps and battery...still no spark?

Are you sure you have a good ground at the plugs? Try a plug clamp wired to the negative terminal of your battery. Turn off the lights in your garage.

You might have lost a ground to the engine.

Again, other than the battery, it is rare an electrical problem happens when your bike is parked....rats, mice, vermin, yes, that happens but electrical problems out of the blue...not often.

After the battery is refreshed, 99% of the no start problems after parked is carb related.

[T Legg]

The most accurate method for determining if there is spark is to have a friend hold the plug while you crank.Another method is to use a timing light.

[Tuned forks]

The most accurate method for determining if there is spark is to have a friend hold the plug while you crank.Another method is to use a timing light.

Of course it helps if the friend doesn't know what tens of thousand of volts feels like coursing thru their hand/arm/body.    I got hit by 60,000 DC one time.  Never forget that feeling.

Joe

[oldktmdude]

   Just re-read this post from the beginning and you have not mentioned anything about fuel. As Noel stated in an early post, the usual cause of a
non start issue after a period of rest, is fuel related not spark. Have you tried putting a small amount (1/2 teaspoon)  of fuel down each spark plug hole, re-fitting
plugs and attempt starting? This will give you a solid starting point for trouble shooting. Be aware of the fire hazard when doing this.
   Regards, Pete.

[AppleJack]

Okay,
I will put a clamp to the plugs and try that, I did worry that the spark plug simply lying on top of the head didn't provide good enough contact.   

Carbs are on there way to RPM for refurbish.  I tried to do it myself but they are in really tough shape; and so after I broke one choke plunger that was essentially welded in place and boogered up the slot in a pilot jet screw, boxed 'em up and sent them to Cali.

Appreciate the help once again...

 

[Bones]

Carbs are on there way to RPM for refurbish.  I tried to do it myself but they are in really tough shape; and so after I broke one choke plunger that was essentially welded in place and boogered up the slot in a pilot jet screw, boxed 'em up and sent them to Cali.

Appreciate the help once again...

 

Don't worry about your coils, I think you've just self diagnosed your problem. Electrical systems on bikes are usually pretty reliable and just don't stop working if not ridden for a while. I guarantee when you get the carbs back and hit the button it'll fire straight up.

[Tuned forks]

Sending your carbs to Robert may be the smartest motorcycle move you have made.  I just sent my second set to him.  You will not be disappointed.

Joe

[rlucas]

^^^^^^  This. You will be amazed.

rossi

[FJ_Hooligan]

Now I'm disappointed.

When I saw that Rock was the latest poster in this thread I was anticipating poking fun at someone with the name of Lucas giving electrical advice.  :-)

Oh well, there's always FB.