Gs750L no spark

[Guest]

Hey guys. I just got a 1980 Gs750L and have no idea why it's not getting spark. Where do I start testing? Please help.

[geol]

Under your seat will be plugs for the coils; the orange/white wire is the power. Pull one of the plugs apart going to the coils and turn your key on. Put a multimeter probe on the O/W pin that feeds one of the coils. If you are getting 12VDC (doesn't have to be running) that is good and the coils are powered. If not, take off your left side cover and find O/W wire that comes out of the fuse box and check it for voltage with the key on. This will tell you if the bike is getting power through the ignition switch as the red wire goes up to the switch hot and comes back and feeds 3 circuits (on my GS1000 anyway). If you have power here on the O/W, you can open up the right handlebar switch and check for power on both sides of the kill switch. The O/W carries power through the switch and comes out and down to the coils. If you have power at all these places you will need to start looking at your ignition and can stop checking the power after the coil connector if there is power there.

OK... not sure what type ignition you have but it is likely points. There is a wire that powers the points and it will also be O/W (just guessing here on the color). Check to see if this wire goes hot when you turn the key on under the points cover. If not, you will have to work backwards through connectors to find where the power is broken as it also comes off the right handlebar switch through the kill switch. If there is power, then more unlikely but the wires feeding the pulse from the coils are the suspect. These wires will be the other wires going to your coils that are NOT O/W and will be two different colors to indicate the 1/4 side of the ignition and the 2/3 side.

If all four plugs are not firing it is far more likely to be an electrical issue than an ignition issue. Of course, you will want to check to see if your battery has a charge before doing any of this. At rest (not running) you should have 12.5VDC or there abouts.

[OldVet66]

Just on the off chance it is simple, check the kill switch, the orange/white wire feeding the coils go through there and I have had problems with solder joints in the switch before.

[ShadowFocus603]

1980 should have the updated ignition. Not points.