1000G suddenly not firing at all

[tkent02]

Magic sucks when you're not the magician.

[motokid837]

Magic sucks when you're not the magician.

You may be clever...but that doesn't give me an answer! Haha if anyone has the answer to this "magic" please assist

[bccap]

Change the oil again after 50 km or so....

[bccap]

You may be clever...but that doesn't give me an answer! Haha if anyone has the answer to this "magic" please assist

Tkent explained it on another thread which I can't find right now. But essentially gas was leaking past a jet that was not designed to hold back the amount it receives on prime. It sounds like it eventually cleared the surplus gas out and operated normally....

[tkent02]

Magic !

[JTGS850GL]

Changing the oil had nothing to do with it other then the time it took to get it all done. My guess is that the excessive fuel that poured into the air filter finally evaporated and allowed you to get it started.

[motokid837]

Yep. Just went out to start it this morning and it is the same thing all over again, after cranking on the starter over and over again it is not starting, I checked a spark plug..it was not wet. So now what.

[bccap]

Did you check the vacuum and fuel outlets on the petcock for leakage ? { in the on position } What colour are the spark plugs ? A pic ? I've had to replace the spark plugs in the past after a starting issue....

[motokid837]

Hmmm...after playing with the choke and trying to start the bike without the fuel lines connected (so it wouldn't be sucking in more fuel) I got it to idle here and there with the choke. Eventually I re-connected the fuel lines and the bike started.

Something is definitely fuel related and since chef rebuilt my carbs, I think I am going to start with the petcock and remove it to make sure its good and cleaned out then go from there..

[bccap]

If the petcock is not leaking when in the on position and gas pours out in the prime position the petcock should not be the problem. Have you checked with out the lines connected ? Draining the float bowls might help as well.

[motokid837]

If the petcock is not leaking when in the on position and gas pours out in the prime position the petcock should not be the problem. Have you checked with out the lines connected ? Draining the float bowls might help as well.

Thats how I got the bike to first start this morning, was once I took off the vacuum and main fuel line, then once it was started I reconnected the lines and it ran...thats what you mean right?

[Flyboy]

Pull the fuel line off the tap, with the bike switched off an not running.
1. In the ON position, there should be no fuel coming out.
2. In the PRIME position, the fuel should run freely.
3.In the RES position, there should be no fuel coming out.

If this checks out, you may have a ruptured diaphragm, in the fuel tap that is allowing fuel to get to the vacuum side and run into the carbs through the vacuum pipe [the thin one], so even though your tap is working correctly, and no fuel is flowing in the ON position, it is running into the carbs via the vacuum pipe and flooding the whole deal.
It would also account for the bike dying after running a very short while, because if the vacuum diaphragm is ruptured, then there will be no vacuum behind it to open the fuel tap once the bike is running, thus dieing as soon as the fuel is used up.

Hope that makes sense.

[bccap]

Thats how I got the bike to first start this morning, was once I took off the vacuum and main fuel line, then once it was started I reconnected the lines and it ran...thats what you mean right?

No, like Stan says, is they're fuel leaking even a little drip when in the reserve and on position, and does the fuel flow freely when on prime without those hoses connected ? And what color are those plugs ?

[JTGS850GL]

Don't say it can't be a float problem even if Chef did the rebuild. I've had a couple carbs that had float valve issues but intermittently. If Chef reused your original float valves (normal procedure) it's very possible that you may still have a float valve problem. Most rebuilds reuse the valve if there are no obvious problems. Worked when it left him but fails later is pretty common problem on a rebuild. I've watched a valve hold pressure for several minutes and then suddenly open and dump fuel with nothing else changing. Just suddenly lets go.

Keep in mind that it takes two failure points to cause fuel to be dumped into the engine. A bad petcock (or on prime) AND a weak or leaking float valve.

I'm at the point where I will now routinely replace the petcock on a bike with no known history. I hate chasing fuel issues let alone two at a time.

[tkent02]

A float valve can't make it leak if no fuel is getting through the petcock.