No power if throttle is turned more than 25%

[82Trashwing]

I have a 1982 GL1100. It was not the best maintained bike. I pegged out the speedometer and then lost all power and RPM's went to an idle. I stopped and saw nothing wrong at a glance. The bike idles and rides fine as long as I only turn the throttle no more than maybe 25%. Any more and all power is lost and the engine idles. It wont go over 55mph on flat ground. Doesn't matter the gear. if I'm riding and turn the throttle open but then roll forward on it it picks back up. My fuel pump has a small leak but it's been running fine for months. I figure it has to be something with the high speed. But I dont want to focus so much on that to where I miss something small. TIA

[Maz]

Check the fuel filter. Is it clogged?
Maz

[MattMcCoy]

My guess is that if the fuel pump was already leaking, that the condition of the diaphragm has become worse and the bike is not receiving enough fuel at higher RPMs. In my opinion, a leaking fuel pump needs to addressed anyway and might help troubleshoot your issue as you check it off the list.

[82Trashwing]

I let the bike sit for 24 hrs. With it on the center stand I revved it in neutral and I could go about 50% throttle. I removed the air filter because I was going to use starting fluid to see if the mixture was too lean but before I sprayed any the bike started working like normal. The air filter wasn't that dirty but I sprayed it out and put it back in. Did about 90 min of riding. Everything seems fine. It seems a tad harder to start now but I think it's unrelated. Does an 82 Goldwing have a limp mode of some kind?

[WingAdmin]

Nope, no computers at all, the engine either runs correctly or it doesn't. Was the filter really dirty?

[LAB3]

Running poorly after having the speedo pegged leads me to believe that a carb float got itself stuck open. Sounds like you need to replace that fuel pump too, it might not be at a point of total failure YET but will be at some point.

[DenverWinger]

Beware that questionable pump, if the diaphragm has any leak it can be pumping fuel into the right side valve cover and the crankcase, too.