Is it still carb problems???

[rvnkvn]

Ok, here we go again...83 GS750es
Having a time trying to figure out why this has left me on the side of the road.
Cold start, perfect. Warm idle, great. Most of the time riding down the road is uneventful. THEN, it starts, bucking and surging. Followed by dropping cylinders, and bogging when giving it throttle.

Gas tank has gas,main tank.I have applied the choke while this happens,helps a touch, but still runs terrible.Thinking it's a fuel problem, I switch it to prime. No change. Sometimes I do make it home, barely, and let it set for about 8 to 10 minutes. Fires right back up, idles great, takes gas when you blip the throttle. Road test again, same thing after a couple of miles down the road.

I've replaced the fuel line, added a filter to the line to the carbs. Replaced the petcock with new. re-checked the tank for debris.Inspected the gas cap and checked the vent..
I have even removed the valve cover, tripple checked the head gasket torque, and valve adjustments.Has Factory air box, Uni filter,stock exhaust system.
What else can I check, Coils, pick up, Ignition box. Is this a vapor lock? Vac line to carb/petcock now new. Intake boots appear to be good. Replaced o rings.
Anyone have any more ideas?

[Nessism]

Fuel flow to the carbs would be my guess. Did you install a fuel filter? Is the fuel line straight and free of kinks?

Maybe ride the bike until it dies than park it and pull off a couple of the fuel drain plugs on the float bowl to check for fuel. Also, bring a spare spark plug so you can check spark right after it dies.

Good luck.

[rvnkvn]

I have pulled the lower faring off the bike, and removed the plus wire from #1 wire before and found spark at that plug. I have not tried 2 or 3 just because it was harder to get to. I'll check the bowl plugs next time..Thanks!!

[keman]

When was the last time the carbs were cleaned properly?? Have you checked all your other electrical connections?? Bad connectors get hot after running a bit and may create more resistance so that the coils get less juice... Don't know...

[jaywelchy]

Not sure, but heard someone else here talk of a vacuum build up in the tank ... take the gas cap off and ride it for a bit??

Good Luck ..
Jason

[rvnkvn]

Carbs,were cleaned, replaced needles, seats, re, jetted, installed stock needles, bench sync'ed, vacc sync'ed. Maybe a bad coil..any way to check this, resistance levels..ect...Kevin

[rvnkvn]

Thought of that too. Removed the cap, fired up the bike along side of the road...NO change.

[OldVet66]

It sure sounds like a fuel line with too much of a bend in it collapsing and cutting off the fuel supply when it gets warm as Nessism indicated.

[rvnkvn]

It makes sense... cause the last time I pulled the tank and installed a remote motion pro tank with a shut off valve, I did not have any problems with it in the garage. I'll look into this after work tomarrow. Guess I'll have to drive in instead of riding the bike