1981 GS450S Igniter help

[Guest]

I currently own a 1981 suzuki gs450s, and have run into a problem with my igniter. The ground wire sparks when it touches the frame so I believe its busted. So when I look online for a new igniter theres pratically nothing popping up. So my question is can you interchange igniters bewteen different brands? Or is there a modern igniter that would fit it? My theory was that since its so old theres not much of a difference bewteen how they are made in that year. But I wasnt sure so thats why im reaching out for help. If anyone knows where I could find one or any other substitutes please let me know. Thanks!

-Rowan

[fbody_mike]

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F401764969918

Gs250 and 1980 gs550l as well as 1980 to 1982 gs450 use the same ignitor. There are a few on Ebay, kinda pricey though.

[John Park]

If you're still running a shunt type regulator/rectifier you might want to upgrade that to a series type [Shindengen SH775] before you spend a lot of money because regulators failing to regulate can fry ignitors. The early mechanical advance ignitors only apply to 80 - 82 so they're scarce. A GS500 setup is far more common, still available new from Suzuki and will probably cost less used, including the fixed rotor, than a by now old and tired original style. The new style ones seem far more robust and reliable. You would have to splice in a new style connector plug tho.

Dyna ignitions are another option. You can even go back to - cough - points......

I haven't tried it, but I think that if the ignition is on, the ground wire will spark to ground without the engine running. Sparks are generated by the current being switched off - think points opening - so the ignitor should draw when the key is on. If your battery is lame on one cell the ignitor won't work when the starter is going - not enough voltage - and the bike will only start just as you take your finger off the button, if you time it right. Was just there a month ago with my '82.

It's hard to know whether the charging system is not regulating properly if the motor won't run, but you can at least run it slow and monitor the voltage; if it goes over 15 as you increase the revs you're in need of a regulator/rectifier.

[Gorminrider]

Does the bike run? If so, why do you suspect the "ignitor"?

as to "sparks"...
Does it spark with key OFF? it should not. Your key switch is the first suspect.
Does it spark with kill switch OFF? it should not. Your kill switch is the first suspect.
Does it spark with key+ kill switch ON? that's ok. The motor must be running to interrupt current through the coils+igniter and thereby create sparks.

[Rowan G]

the reason were suspect is because the ground wire coming from the ignitor is sparking when touching the frame of the bike, which I believe is something it shouldn't do. Plus we eliminated almost everything else it would be. Solenoid is good, starter motor is good, etc. we know all the switches (key, run/off switch) are working. We connected the wires and when turned on we could see the circuit was complete.

[Rowan G]

thanks man, ill look into wether my regulator is up to standards, if not ill take a look at the Shindengen. And yeah when online any igniters are easily 100$ or more

[pdqford]

I currently own a 1981 suzuki gs450s, and have run into a problem with my igniter. The ground wire sparks when it touches the frame

-Rowan

Shouldn’t the ground wire be firmly attached to ground so that it doesn’spark?

[pdqford]

Does the bike run?.

Ditto."..........

[John Park]

the reason were suspect is because the ground wire coming from the ignitor is sparking when touching the frame of the bike, which I believe is something it shouldn't do. Plus we eliminated almost everything else it would be. Solenoid is good, starter motor is good, etc. we know all the switches (key, run/off switch) are working. We connected the wires and when turned on we could see the circuit was complete.

What leads you to believe it shouldn't? How could you see the circuit was complete? Which circuit? The best test of an ignitor is another, known to be good, ignitor being substituted an the bike runs. If you spend xxx$ on a 'should be good but used' ignitor and it still doesn't work.......

Do you have a multimeter?