Troubleshooting No Star After Carb Rebuild

[n780]

Pretty frustrated, here's the situation:

1983 GS400E

Battery is good
Spark gaps are good
Gas is new
There is fuel in the floats
Engine sounds like it's turning fine
Good compression out of the exhaust.

No hint on ignition, pops, backfires or anything. It'll just turn and turn until it'll kill the battery. Handlebar killswitch is on 'run' and there's no kickstand switch.

What could I be missing?

 

[Agemax]

check to see if the plugs are wet, with fuel. if not you have no fuel getting to the cylinders

 

[Steve]

Not starting after a rebuild is quite often due to not having the idle speed set correctly. Try adjusting the idle speed knob until something happens. Do this after verifying whether your plugs are wet, as Agemax has suggested.

Just for your information, the kickstand switch has NOTHING to do with whether the engine runs or not. It's ONLY function is to turn on a light in the instrument panel.

.

 

[n780]

Ok, I cheated a bit and used a quick spray of starter fluid. It turned over quickly but then fuel started pouring out of the carbs somewhere
A float needle problem? I guess back off the bike they come...

 

[n780]

Up and running! Two culprits:

1) The $8 valve seats just weren't cutting it. The $25 OEM ones had the float working the way it should.

2) My petcock won't prime, time for a new one. But on flows properly with a vacuum. Had to suck on the vacuum hose for a while until the bowls filled.

Feels good to be rolling again.

 

[Guest]

Up and running! Two culprits:

1) The $8 valve seats just weren't cutting it. The $25 OEM ones had the float working the way it should.

2) My petcock won't prime, time for a new one. But on flows properly with a vacuum. Had to suck on the vacuum hose for a while until the bowls filled.

Feels good to be rolling again.

Sometimes a petcock will need alittle vacuum to just get it going on prime, once started you have to manually turn it off though

 

[Steve]

Sometimes a petcock will need alittle vacuum to just get it going on prime, once started you have to manually turn it off though

I have only noted that on the "dreaded '80 petcock", the one without the lever. :-k

The OP has an '83, so it should work by merely turning the lever.

Either way, the important thing is that it has been resolved.

.