80 XS1100G runs rough full throttle only

[Radioguylogs]

Sorry, hope I didn't insult you.

I didn't expect cyanoacrylate could be melted.

[ernie elmore]

Ernie here with XS1100 stutter.
Last year the bike fell over starting a left hand turn from a stop. Got bike up but was flooded and would not start. Lucky I was on a hill, so paddled downhill and the bike sputtered, coughed, cleared and started. I then noticed the stutter at full throttle. So I pulled the carbs, sprayed and blew out all jets and passages.

The carb slides have new JBM diaphragms installed last year which worked great when new. The diaphragms on #1 carb had pulled 1/2 way out of the slide grove. So I reinstalled that diaphragm and all other diaphragms seemed to be tight on the slides. So replaced and synced carbs. Bike seemed to run fine.

Bike was not ridden for a while due to ankle fusion. Had to clean carbs again. Diaphragms seemed to be tight. Then I noticed the Stutter at WOT between 2000 - 4000 rpm was back again.

Do you think the JBM Slide diaphragm(s) could be leaking vac around the slide grove and not lifting a slide as far as the other slides???
The JBM Diaphragms have a tight fit on the slide with NO ring or keeper in the slide grove. What would be best way to seal the JBM diaphragm in the slide grove?

[jetmechmarty]

Have you eliminated all electrical possibilities? It still sounds like it could be loss of spark to me.

If the tops of the carburetor bodies are unblemished and the covers are flat, the JBM diaphragms should seal up just fine.

[motoman]

Unfortunately your carbs are still havin' electrical issues.......that would be primary, secondary or both........need to do some voltage checks, startin' with voltage TO coils, key on. You also haven't stated whether ballast resistor is still in system or by-passed.

[MPittma100]

Ernie here with XS1100 stutter.
Last year the bike fell over starting a left hand turn from a stop. Got bike up but was flooded and would not start. Lucky I was on a hill, so paddled downhill and the bike sputtered, coughed, cleared and started. I then noticed the stutter at full throttle. So I pulled the carbs, sprayed and blew out all jets and passages.

The carb slides have new JBM diaphragms installed last year which worked great when new. The diaphragms on #1 carb had pulled 1/2 way out of the slide grove. So I reinstalled that diaphragm and all other diaphragms seemed to be tight on the slides. So replaced and synced carbs. Bike seemed to run fine.

Bike was not ridden for a while due to ankle fusion. Had to clean carbs again. Diaphragms seemed to be tight. Then I noticed the Stutter at WOT between 2000 - 4000 rpm was back again.

Do you think the JBM Slide diaphragm(s) could be leaking vac around the slide grove and not lifting a slide as far as the other slides???
The JBM Diaphragms have a tight fit on the slide with NO ring or keeper in the slide grove. What would be best way to seal the JBM diaphragm in the slide grove?

The manufacturer of the aftermarket diaphragms that I have used recommend Super Glue to seal them to the slides. Another electrical area to check is the air gap for each pickup coil.