1981 gs 650 l

[superradioman]

Using Clymer as a reference first swaped leads to coils one did not fire. Replaced with new aftermarket coil still firing on 2 cyl. Did the test found signal generator coil measured 360 ohm as book said. Did test with ohmeter to fire ignitor no spark Ok ignitor bad bought "good used" and carefully installed still only spark on two cyl and test on used module indicates bad ignitor.Do these CDI units all fail on only two cyl? Am I missing something? Can I install the seperate coils and ignitor from a chain drive model as parts becoming impossible?

[tom203]

Welcome,but slow down! The ignitor on this model is very durable, it's usually the connections between signal coils and ignitor and from there to ignition coils that problem arise. Also, often the plug caps are no good. the stock ignition coils measure about 4 ohm primary resistance, what about your aftermarket ones? Is this bike new to you??? And which two cylinders ain't firing?

[superradioman]

81 gs650

Cleaned all connections and carefully installed the used ignitor. I've had the bike 6 years and ran great till about 2 months when after it sat for several months this problem showed. The coil I replace was Left side for 1&4 but I have swapped the wires and when fed by rt side leads it fires with a good spark but only when cranked with starter . The battery or ohm meter test never produced a spark either when the connection was made or pulled per Clymers. They say bad replace if either side or neither fires and this was the case with the used part which I've returned to seller.Plugs and voltage reg are the only electrical parts replaced.

[tom203]

OK, you cleaned the two plugs that connect stuff to ignitor -one right over battery( from signal coils) and one just above air filter box (feeds 12 volt to ignitor and connects ignitor to negative side of ignition coils). What voltage do you have on orange/white wire on coils ( from wire to good ground) ?
Try this Mr. Matchless test; remove signal generator cover, see the little tab that swings by the signal coils? with ignition on,duplicate what the tab does, by swinging a small screwdriver blade first by coil face for 1 and 4 -this disrupts the magnetic field and causes 1 and 4 to fire, repeat for 2 and 3 signal coil to get 2 and 3 to fire. Of course, no test will work if the connections are corroded.

[BassCliff]

Greetings and Saltuations!!

Hi Mr. Superradioman,

Start here: Testing The Ignition System, then see the other troubleshooting tips on that page. Make sure all the other maintenance is checked and up to date. Here's your "mega-welcome".

If you are here you probably have a 30 year old motorcycle that needs about 20 years worth of maintenance. You'll find all kinds of helpful tips, procedures, manuals, diagrams, "how-to" guides, etc, in the links below. Let's get started.

Let me dump a TON of 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. This is what NOT to do: Top 10 Newbie Mistakes. 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!

More links to helpful threads in the forum:
Help! Your Bike Won't Start
DON'T DO THESE THINGS
Help! Your Bike Won't Run Well
Oh God! Pods!


Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[superradioman]

1981 gs 650 l

After once again checking for continuity between signal gen and ignitor (0 ohms) and measuring coil voltage 12 + I removed signal generator cover which appears to have never been off and spotless inside I passed a screw driver blade between the poles and found that regardless which pole it fired the 2-3 coil and never the 1-4 coil. This is after having tried a used one which I have allready returned on the belief that it had the same defect as my original ignitor which I carefully reinstalled today before starting measurements and test. Once again I see no other conclusion other than that both my ignitor and the used one were both bad. It is odd though that the screwdriver test produced spark on 2-3 only just as when i use the starter but the application of 1 1/2 volts with out cranking never produced any spark on either coil. Help have I really had 2 bad ignitors in a row or is there still a gremlin?

[tom203]

I'm grasping at straws here so bear with me!. The signal coil for 1 and 4 - does it behave like a magnet (grabs metal -about the same as coil for 2 and 3) ? It sure sounds like both ignitors are NG, but why on same side of ignition.

[superradioman]

1981 gs650 l

Sure does strong magnetic attraction to my screwdriver and no matter which coil I pass by with the screwdriver I get a good solid spark on the 2-3 coil. I even tore the kill switch apart and checked it for ground tracks remembering my previous GS 650 E had corroded once as that bike sat out in the weather.At the point now where there is little left except to think that like some of the Japonese electronics that our shops serviced the power supplies all died of electrolytic capacitor failure at about the same time ans some where buried in the epoxy of the ignitors are large value caps that fire the coils.Last week there were 5 units on EBay now only 1 left and it is in Norway so I guess I wait for another to appear short of an offer of one for sale from another GS owner.

[tom203]

Another poster in this forum (scroll down to "No spark" title ) has similar problem on a gs850 -no spark on 1 and 4. He believes he's got a faulty pickup coil.
Anyways, I know I got two spare ignitors- untested because of my status with the "If it ain't broke, don't fix it club". I'll dig them out and run them on my bike and see if they are functional.

[superradioman]

1981 gs 650 l

It will sure be interesting to see if yours work after long storage. Mean time i will just wait for another appears on EBay or after the next SS check if it is more expensive than the $49 one I returned. Google search last nite found new genuine Suzuki for $485 NO WAY.

[tom203]

It will sure be interesting to see if yours work after long storage. Mean time i will just wait for another appears on EBay or after the next SS check if it is more expensive than the $49 one I returned. Google search last nite found new genuine Suzuki for $485 NO WAY.

"long storage" ? Both my spares worked wonderfully, just like Mr. Suzuki intended! Both fired all 4 right up ,idled nice and survived 20 minute ride as test; no sign of heat after 4 mile 60 mph burst.
I figured these things use a pair of (mos)FETs as switches- gate triggered by a signal circuit. What ever you do, your make sure your charging voltage is not too high- run the stator paper tests.
Send me a PM if you are interested in one of my pretested ignitors.

[superradioman]

1981 gs650l

Finally today after long hours thanks to Toms ignitor module and a whole new set of ground wires as well as 1 new coil I was able to go for a short ride. Will never know whether a bad coil (primary measures 2 ohms)destroyed the ignitor or the reverse but both were bad. There is also the possibility that jumping the battery from my car may have started the failure of both. The lesson learned is dont jump from a car and check all grounds.Still need to sort out the carb linkeages and adjustments but it is now rideable.

[tom203]

Have some ice on standby for that new-to-you ignitor- it might not like the Florida weather! Also, when you can,update your signature (upper left "User CP" ) to let the forum members, know about your past bikes - this gives inspiration to the youngsters sorting out their bike's problems.
Good to know it's "rideable" !