Bike starts then shuts off immediately

[Guest]

Hey guys,
I have a 79 GS1000 with a newish battery (5-6 months). I can start the bike just fine but as soon as I let go of the starter switch the bike dies. I have a new rectifier on the way. Is this something that the rectifier with fix or is this a separate issue?

[kdo58]

take the gas tank off and start looking for melted connectors, and look in the head light bucket

[williampkerr]

How long have you had this bike? Have you ever had the bike running without this issue? Has anything changed on this bike before this issue arose? I'm trying to determine your history with this bike, like did you just recently acquire this bike and are now trying to fix this problem that was already present or did you do something to it recently that might have caused this problem?

[nathanmaus]

I have had this bike for about a year. I haven't had this problem before. Recently my bike hasn't held a charge. I can ride for about 2 hours before I have to put it on a trickle charger. I tracked that back to the Rectifier and have a new one coming in. I haven't rode for about a month because I've been out of town and was waiting on a few parts.

I just relocated and rewired the starter switch and kill switch. I used the original wiring for this. It was wired up to a momentary push button and the kill switch was wired to a normal rocker switch.

I just had the gas tank off and didn't see any melted connections but I'll look again. I'll also check the headlight bucket.

[nathanmaus]

take the gas tank off and start looking for melted connectors, and look in the head light bucket

Which connectors would create this problem?

[JTGS850GL]

How about answering the history questions first. How long have you owned this bike? Did this problem suddenly happen or has it always been there since you've owned it? What maintenance have you done up to this point? Have the carbs been cleaned? Choke working?

Basically we need some more detailed before any meaningful suggestions can be made.

Edit: I went back to your previous posts and found that you just recently purchased this bike in "not running condition". You were complaining that the idle would go straight to 7K rpms and stay there. What have you done between then and now in order to have the newest problem occur?

[stetracer]

Put the gas valve on prime and try it.

[nathanmaus]

How about answering the history questions first. How long have you owned this bike? Did this problem suddenly happen or has it always been there since you've owned it? What maintenance have you done up to this point? Have the carbs been cleaned? Choke working?

Basically we need some more detailed before any meaningful suggestions can be made.

Check post #4 I went into the history there. Carbs were cleaned probably 2 months ago so I may need to take those out and clean them again. This problem just started happening yesterday. When I bought this bike it didn't have a choke actually, but I've never ran into this issue.

[JTGS850GL]

Check post #4 I went into the history there. Carbs were cleaned probably 2 months ago so I may need to take those out and clean them again. This problem just started happening yesterday. When I bought this bike it didn't have a choke actually, but I've never ran into this issue.

Then lets start out with doing the basics. First off, get the valves adjusted. They will effect more then you would think. These bikes are pretty sensitive to tight valves. After that, the do a COMPLETE and PROPER strip and dip on the carbs. Replace ALL the O-rings. Do a proper bench sync and then a dynamic sync. Get that choke working correctly as well. It's really not an optional part. Normal start procedure would be to put the engine on choke and don't touch the throttle at all. Blipping the throttle can cause it to die when cold. If the rpms go much above 2-3K then back off the choke a little. When you can idle off choke then you're good to go.

As for this newest problem, can you give us a little more detail about exactly what happens when you stop pushing the start button? Does the idle go up as long as you're pushing the starter button or does it just seem to want to start but never goes much above the starter speed?

I'm betting that the idle adjustment is set way to low and you're not using the choke properly.

[nathanmaus]

It starts just fine if I'm pushing the starter button. As soon as I let it off it dies. It's probably idling right around 1k, that's approximated by sound since I got rid of the old tach and speedo and switched to a digital speedo awhile back. As soon as I let off the starter switch it dies, whether I leave it at idle or give it some throttle.

I haven't had issues before with not having a choke. I just have to give it a little throttle while it's warming up.

[Steve]

I just relocated and rewired the starter switch and kill switch. I used the original wiring for this. It was wired up to a momentary push button and the kill switch was wired to a normal rocker switch.

There are three wires in a connector that goes to the 'kill' switch and starter button. Two of the wires are the same color, but one of them has a red band around it at the connector. Check the order of those three wires against a wiring diagram. It is my suspicion that your ignition wire (which should only be controlled by the 'kill' switch) is also tied in with your starter.

.

[JTGS850GL]

Strange issue since the starter circuit has nothing to do with ignition circuit other then they share the same power source. If that wasn't in place then the starter wouldn't work either. The Orange/White wire supplies power to the ignition system. Verify voltage at the connectors going to the coil as well as the one going to the ignition module. You might want to check all the grounds as well.


Just curious if you have a way to post a video of the bike trying to run with the start button on and then off?

[JTGS850GL]

There are three wires in a connector that goes to the 'kill' switch and starter button. Two of the wires are the same color, but one of them has a red band around it at the connector. Check the order of those three wires against a wiring diagram. It is my suspicion that your ignition wire (which should only be controlled by the 'kill' switch) is also tied in with your starter.

.

Good catch. Didn't see that post and it wasn't in this thread. No mention of a rewire job in this thread at all. That's a key to solving this problem I think. If there was some "creative" rewiring in the area of the start button and engine kill switch then that would surely cause issues like this.

Nathonmous: Don't assume that every thread you've written here is read and remembered by others reading a different thread. When a new thread is created then it's best to assume that some or all history has been lost from a previous thread.

[williampkerr]

I just relocated and rewired the starter switch and kill switch. I used the original wiring for this. It was wired up to a momentary push button and the kill switch was wired to a normal rocker switch.

I'm with Steve on this suspicion. The starter button/kill switch housing is apparently the only thing that has changed or rewired recently. Definitely use your wiring diagram to verify your connections. I've had electrical issue recently (newbie myself) and all have been traced back to bad rewiring on my part.

[nathanmaus]

Nathonmous: Don't assume that every thread you've written here is read and remembered by others reading a different thread. When a new thread is created then it's best to assume that some or all history has been lost from a previous thread.

Thanks guys I'll look into this wiring again, I provided this info in post #4 on this thread with the rest of the history as well.