Weird ignition issue

[Guest]

Here goes, I have a 1980 gs450l. it has a new battery. it will start and run but not without a jump from a battery charger. And when it does run it has a random misfire on right cylinder. even after cleaning the carbs. when i turn the key on its fine, but as soon as I turn the run switch on, it immediately starts draining the battery. I have checked and rechecked all wires and connections. coils are within spec on ohmmeter. I have found that the black ground wire coming out of the igniter is producing 12v battery voltage when the run switch is turned on. Should this ground wire be producing voltage? Am I missing something here or do i just need a new igniter?

[tom203]

When you turn run switch "ON", power starts flowing to ignition coils and ignitor, so there is an immediate battery drain. But since your bike doesn't start without help (booster), you probably have charging/connection problems to fix. Low system voltage makes for an unhappy ignitor- i.e. misfire. have you seen and done the "Quick Test" in this link??

http://www.thegsresources.com/_forum/showpost.php?p=1138531&postcount=1

If you report your results of the test, it might help. Make sure you start with fully charged battery.

[barnbiketom]

I don't know what 'wire' you are measuring, if it is BLACK with WHITE tracer then that may be as it is the signal generator circuit, NOT a ground.
and what Tom said above. do it

[posplayr]

Here goes, I have a 1980 gs450l. it has a new battery. it will start and run but not without a jump from a battery charger. And when it does run it has a random misfire on right cylinder. even after cleaning the carbs. when i turn the key on its fine, but as soon as I turn the run switch on, it immediately starts draining the battery. I have checked and rechecked all wires and connections. coils are within spec on ohmmeter. I have found that the black ground wire coming out of the igniter is producing 12v battery voltage when the run switch is turned on. Should this ground wire be producing voltage? Am I missing something here or do i just need a new igniter?

Sorry but this is a classic example of performing tests without having any idea of what to expect and much less how to interpret any thing else abnormal! Why do pèople do these types of tests?


If you turn the key on and power the ignitor current want to flow through the ignitor to groun through multiple paths. If you open the ground wire sure enough the wire will go to +12v. Unless you have something very specific that you need to determine by someone that is probably much more knowledgeable there virtually no reason I can see for ever doing this type of test!!! Why do it? How did you even arrive at doing something like this?

If nothing else try and find a qualified reference and follow that test advice. Generally it is better if it is specific to your bike. If all else fails read the manual. In this case run the "Quick Test"

[p_trice]

bike failed the quick test. 8v at idle. 11v at 5k

[posplayr]

bike failed the quick test. 8v at idle. 11v at 5k

Battery is dead

[terrylee]

Do the rest of the tests and figure out if it might be r/r or stator or both. Also clean all wire connectors and replace any that look burnt or brittle. terrylee

[posplayr]

Do the rest of the tests and figure out if it might be r/r or stator or both. Also clean all wire connectors and replace any that look burnt or brittle. terrylee

Tests require a decent battery and not 8v under standard load