1980 gs ignition coil question

[wowitsseamus]

I just purchased a 1980 gs550 and was told it needs a new ignition coil. would I be able to use a universal 12v coil for this bike seeing it should have cdi right? If not all i can seem to find is sketchy used ones or out of stock catalog items from random distro.

[mike_of_bbg]

You should verify that the coil is bad first. Wiring and ignitors (and plug caps!) are more frequently suspect than the coils themselves. If you need a new coil, a 3 ohm primary dual output coil is what you want. The Dyna green coils are a popular choice:

http://www.z1enterprises.com/detail.aspx?ID=210

Bandit and some GSXR coils have been used successfully in the past. Any of them might require a little light fabrication for mounting.

If a coil is bad, then either 1&4 or 2&3 won't be sparking. Try swapping the leads to the coils and see if the no-spark condition moves. If not, IT IS a coil problem. You can also disconnect the coils and check resistance on the primaries via the connection, or on the secondaries between the plug pairs noted. Primary resistance should be 3-5 ohms. The secondaries are ~15k ohms, but the plug caps add normally ~10k for stock or ~5k for the recommended NGK replacements, for a net of 25k-40k ohms. You can remove the plug caps and check the wire cores separately. The resistors in the caps often go bad with age.

Also check your voltage across the coils, as they're plugged in with the ignition on. Low voltage can cause bad spark, but isn't the coil's fault.

[Nessism]

EDIT: mike posted while I was typing.

I suggest you verify the need for a new coil before changing anything. Could save you some money. The factory service manual should help you test the system. You can download the manual for free from basscliff's web site. Also, your bike does not have a CDI, it has what Suzuki calls a "transistorized" ignition, which is different.

If you do wind up needing new coils, you need to get the type with the appropriate resistance otherwise your ignitor can fry. Again, the factory service manual has details. The most popular coils are the Dyna green units. Z1 Enterprises sell these for a fair price.

[wowitsseamus]

fellas thanks for the input I'll see what I can figure out.

[BassCliff]

Greetings and Salutations!!

Hi Mr. wowitsseamus,

Have a look in the Electrical Odd and Ends section of my little website for ignition troubleshooting procedures. There are two coils on your bike. Normally the left one fires plugs #1 and #4 while the right coil fires plugs #2 and #3.

Anyway, let me dump a TON if information on you and share some GS lovin'.

I just stopped by to welcome you to the forum in my own, special way.

If there's anything you'd like to know about the Suzuki GS model bikes, and most others actually, you've come to the right place. There's a lot of knowledge and experience here in the community. Come on in and let me say "HOoooowwwDY!"....

Here is your very own magical, mystical, mythical, mind-expanding "mega-welcome". Please take notice of the "Top 10 Common Issues", "Top 15 Tips For GS Happiness", the Carb Cleanup Series, and the Stator Papers. All of these tasks must be addressed in order to have a safe, reliable machine. Now let me roll out the welcome mat for you...



Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[straycat]

Hello,

Have you actually looked at your ignition pick up. 1980 gs 550s have points unless they've been upgraded. May just need new points/condensers

sc uk

[Nessism]

Hello,

Have you actually looked at your ignition pick up. 1980 gs 550s have points unless they've been upgraded. May just need new points/condensers

sc uk

1979 was the last year for points in the US market. England, and other places too maybe, may be different though.

[straycat]

Yes,I stand corrected.

sc