GS450 on one cylinder

[eliotsajerkface]

So I thought i had the bike up and running just fine. it revs with no hesitation, but does take a bit to start in the cold, 40 and below. I figured it was just the nature of the beast. yesterday, me and my wife were out riding, her on the 450, me on my 1100 and i noticed she was way behind in my mirror. i pulled over and she said she had the throttle all the way down and it didn't go past 50.

I started it up, pulled the left (driver side) plug wire, and it kept going. pulled the right side plug and it died immediately. We made it to a walmart since i didn't have a small flathead on my bike, and i adjusted the fuel air out a bit on carb 1, like 1.5 turns and fired it up. pulled the right plug and it died. Left it out, pulled the choke out and could get it to cough a bit. if i sucked on the carb one overflow tube, it fired right the hell up. I also noticed if i blocked it, it ran a bit more constant so i threaded a screw in the tube so it would get her home.

She was able to overtake my 1100 on a straightaway when i wasn't paying attention and we cruised at around 75 no problem.

What the **** is going on.

[DimitriT]

Those aren't overflow tubes. They're vent tubes. When the bowls fill with fuel the air
has to go somewhere.. it goes out of those tubes. Likewise, as the fuel is used up the air comes back in through those tubes.

Sucking on the tubes may cause the needle valve to open and fuel to run into the carb. Maybe the float or needle valve got stuck shut and caused your carb to run dry. Plugging up the air vent may cause fuel to stop flowing into the carb. I can't see how that would help you.

How long has it been since the carbs were cleaned?

[eliotsajerkface]

they were "cleaned" pretty recently. i got what i could, but some things were stuck pretty bad and no amount of pb blaster would free them.

[doctorgonzo]

they were "cleaned" pretty recently. i got what i could, but some things were stuck pretty bad and no amount of pb blaster would free them.

Don't know your skill level, but personally I was always intimidated by the idea of tearing carbs down, but it's really not that bad. Good pictorial guides out there, and it will save you a lot of future cursing to just do it. A good tear down/cleaning.

[eliotsajerkface]

i was able to tear down and rebuild the carbs on my gl1100 just fine. I was in a hurry when i did these and the PO had put RTV freakin everywhere so it's a pain to get the boots off. Also, the pain of getting the carbs out to begin with.

[chef1366]

I hope you're not Eliot.:-D

[eliotsajerkface]

i am elliott, but it's just been my sn for everything for a very long time. in college i was a pretty big jerk and someone called me a jerkface, thought it was funny and it stuck.

[eliotsajerkface]

i think i figured it out. tonight when i went to start it, and there was pressure from trying to start the bike, i noticed gas leaking from bowl 1. got the screwdriver over, and tightened the hell out of the bowl and like magic, gas leak stopped, and the bike started. so, i had on helluva air leak and when the bike finally got started before, there may have been enough pressure to pull the bowl into place hence, low speed = crappy running, most high speed = fine running. also may explain clogging the vent tube having an effect on creating a better vacuum inside the bowl.

[eliotsajerkface]

on another related topic, I also found out the PO did a home crap wire job to the battery too. Spliced in some 16 gauge wire and twisted two ends together...awesome. I went out and got a waterproof blade fuse and some 10 gauge wire and redid that. it seems to have more cranking power now so that's a good thing.