Intermittent sputtering

[Paul F]

My 1982 GS1100 has been coughing ever since the head gasket was replaced. It runs great for a while than it starts to cut out for a second and then continues to run fine. It started out only at 5k RPM a few months ago. Now it has become more evident at all speeds accept idle. I installed new coils, wires and plugs in April.
Does anyone have any recomendations on what the problem is?

[fgh]

Perhaps you have a fuel starvation issue. Try driving with the petcock on "PRI" and see if there's any difference. Pull the tank when its not full and lean it so you can remove the petcock without spilling. Look for debris on the screen and a good flow in the valve. Check for a clear line and make sure there are no kinks. LOL!

[Paul F]

Thanks for responding.
I have driven with it in th PRI position but it still has the same problem. I thought about removing the petcock. Is it pretty easy? Do I have to take apart the petcock to check the screen?

[jimcor]

If your tank is full you'll need to drain it. Then remove the tank and unbolt the (probably) two bolts holding the petcock on the bottom of the tank. Just be very careful, you don't want to go breaking any bolts removing them or over-torquing them when installing them.

No, the petcock will not have to be disassembled to clean the screen.

This could be a petcock problem from the sound of it. Also check your gas cap to make sure the vent is operating properly.

[rgierer]

just a couriosity but were valve clearances checked since the head gasket?

[Paul F]

Yes. They were checked when the head gasket was changed.

[prxbadger]

flat battery? get it sometimes with low battery cos cant cope especially with lights on

[Dave8338]

Thanks for responding.
I have driven with it in th PRI position but it still has the same problem. I thought about removing the petcock. Is it pretty easy? Do I have to take apart the petcock to check the screen?

Have you checked the intake boots and all the air boxt fittings to see if they're tight? They might be drawing in air and making the mixture lean enough to misfire. Did you do the intake or did you have a shop do the work? 8-[

[GS850_Coug]

Because it is progressively getting worse, my suspects would be gasket/oring in the intake area, or dirty fuel, plugging up screens. I would also check the torque on the head bolts. It's possible they were torqued in the wrong sequence to begin with (outside to inside, instead of inside to outside). Crack 'em loose again and retorque. I also agree with badger, if there is a faulty stator/rr causing a no charge (or low charge).

[Dink]

BTW valve clearences should have been checked/adjusted again at 600 miles, and the head re-torqued.

Dink

[Paul F]

I have put on about 600 miles since the rebuild. Do you think the sputtering is from not re-adjusting the valves and re-torqueing the head?