Looking for a miracle...

[Gumbo76]

I don't know how much luck I'll have, but I am desperately looking for a Free/REALLY cheap Coil Pack. I was riding my '79 550 back to work at lunch today and lost one cylinder. I get spark intermittently (sp?). I am guessing it is the coil Pack. I really have not had time to dig too deep as I am still at work and will probably be walking my a$$ home tonight. But as soon as I get it back to home base, I will try to dig deeper.

Right now it is running on three cylinders. The #3 (from left to right) is the one acting up. While it is idling, I pull the spark plug wire out and hold it and occaisionally I get a spark. Can't imagine it is the Plug Wire. And it is most likely NOT the Spark Plug itself. I hope to know more tonight.

I am so tempted to just give it up... Ugh .

So if anyone has or knows someone who has a spare kicking around and is willing to help me out, I would greatly appreciate it. If you might have an idea that it may be something else, feel free to chime in. Thanks in advance.

[Dogma]

Well, there are only two coils. The coils fire in pairs, even though the cylinders don't. The plug caps are known to fail as they get old. NGK replacements from Z1 Enterprises are only a few bucks each. Unscrew the old caps and trim back the wire about 6 mm or until you get clean metal before screwing the new cap on.

For today's emergency, examine the cap on the non-sparking cylinder ans see if it looks cracked or otherwise defective. Unscrew it from the wire, and maybe trim some wire to make sure you have a good connection to the cap. If the cap itself looks to have failed, improvise as required.

[rustybronco]

Break out a vom and measure the resistance of the plug cap.

http://www.thegsresources.com/_forum/showthread.php?t=145590

[jpaul]

I don't know how much luck I'll have, but I am desperately looking for a Free/REALLY cheap Coil Pack. I was riding my '79 550 back to work at lunch today and lost one cylinder. I get spark intermittently (sp?). I am guessing it is the coil Pack. I really have not had time to dig too deep as I am still at work and will probably be walking my a$$ home tonight. But as soon as I get it back to home base, I will try to dig deeper.

Right now it is running on three cylinders. The #3 (from left to right) is the one acting up. While it is idling, I pull the spark plug wire out and hold it and occaisionally I get a spark. Can't imagine it is the Plug Wire. And it is most likely NOT the Spark Plug itself. I hope to know more tonight.

I am so tempted to just give it up... Ugh .

So if anyone has or knows someone who has a spare kicking around and is willing to help me out, I would greatly appreciate it. If you might have an idea that it may be something else, feel free to chime in. Thanks in advance.

http://www.thegsresources.com/_forum/showthread.php?t=145973

[Gumbo76]

JPaul,
thanks for posting the link to my "FREE PARTS" thread . Perhaps I have something to Barter with... It took me some time to figure out why you posted my Link. LOL!

-Gumbo

[jpaul]

JPaul,
thanks for posting the link to my "FREE PARTS" thread . Perhaps I have something to Barter with... It took me some time to figure out why you posted my Link. LOL!

-Gumbo

DOH. That's what happens when I'm scanning threads quickly in between doing paperwork that's trying to put me to sleep at work.

As the saying went on Saturday Night Live, Nevermind.

[Nessism]

If only one plug is not firing it's not the coil as the others have mentioned. Also, voltage to the coils is a problem on bikes with corrosion in the wiring harness. Basscliff's site has an article on how to add a relay for feed power to the coils. There is always a solution, you just need to seek it out.

[TheCafeKid]

Did you check the plug boot?? Ive actually had them come apart after getting wet (yes, they were old)

[spyug]

Before jumping to a new coil I would do as Nessim suggests and try the coil relay mod. For a $6 or $7 part it could be a cheap solution for you.

While you are at it, take time to clean and or replace all connectors and contacts that look dirty or corroded. As you no doubt know, corrosion creates resistance in the circuit ( causing voltage drop) and low voltage at the coil could be an issue.

The coil relay mod is not difficult and well worth doing IMHO.

Good luck with it.

cheers,
Spyug