I have a sort of similar problem to RHHarrison in this post. I have a '90 GL1500SE that just recently came into my possession that has been sitting a few years. I could hear it kicking over and was able to adjust the idle knob until it would idle. It has a new fuel filter and a tank full of fresh gas that I dumped the better part of a can of seafoam into. The petcock was leaking fuel, so I rebuilt it and made sure it was working properly. The vacuum pressure to the petcock seems to be good at 500+ mmHg, and fuel does flow out. I've been starting it up and letting it idle for 20-30 minutes at a time slowly backing off the choke, but I just can't seem to get it past 15-20% up before it dies. Increasing the throttle also causes it to die.
My next guess/step is to yank the cabs and have them cleaned/rebuilt, but I have a question. I noticed that when I back off the choke to the point of the bike dying, and then reapply it, that it seems that there is a whoosh of vacuum release tied to that action. Is that consistent with anything or normal?
Another full choke runner
- RockportDave
- Posts: 427
- Joined: Sat Mar 31, 2018 9:39 pm
- Location: Rockport Texas
- Motorcycle: 1999 GL1500 SE
Previous bikes:
1969 Honda CL90 “bobbed” before it was cool
1981 Yamaha 850 Triple w/Windjammer
1981 GL1100 Interstate
1985 GL1200 LTD
1988 GL1500
1988 GL1500
Re: Another full choke runner
Welcome to the forum.
The choke is really an enrichment that allows more fuel into the carb.
If it sat a while it probably needs a carb rebuild and possibly vacuum lines replaced.
Mine had sat a lot of its life before we got it and it had a rough idle and lack of power. I finally pulled the carbs (3rd time), soaked them in carb dip, installed new jets, o rings, accelerator pump kit and new carb isolators. Balanced the carbs and did the idle drop. It runs great now. I also checked all the vacuum lines while in there and found one with a hole.
I wanted it to be dependable so I spent the money and time to do it right.
Dave
The choke is really an enrichment that allows more fuel into the carb.
If it sat a while it probably needs a carb rebuild and possibly vacuum lines replaced.
Mine had sat a lot of its life before we got it and it had a rough idle and lack of power. I finally pulled the carbs (3rd time), soaked them in carb dip, installed new jets, o rings, accelerator pump kit and new carb isolators. Balanced the carbs and did the idle drop. It runs great now. I also checked all the vacuum lines while in there and found one with a hole.
I wanted it to be dependable so I spent the money and time to do it right.
Dave
1999 GL1500SE 5th Goldwing through the years
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- Posts: 8
- Joined: Mon Apr 01, 2019 4:48 pm
- Location: Oviedo, FL, USA
- Motorcycle: 1990 GL1500SE
Re: Another full choke runner
So I finally got the carbs off the bike yesterday to try to rebuild them. The vacuum lines are not looking the greatest, and I want to just replace as many as I can while the carbs are off. I am finding some difficulty locating the correct size hoses to order...
Does anyone know where I can find these on the diagrams in Partzilla? I saw WingAdmin over here showing three sizes (3.2/4.2/5.8 mm). where's the best place to find these as amazon seems a bit limited?
Does anyone know where I can find these on the diagrams in Partzilla? I saw WingAdmin over here showing three sizes (3.2/4.2/5.8 mm). where's the best place to find these as amazon seems a bit limited?
- bellboy40
- Posts: 799
- Joined: Fri Nov 27, 2009 1:13 pm
- Location: Brewton, AL
- Motorcycle: 2000 GL1500SE Candy Spectra Red
Re: Another full choke runner
Try these links and see if you can find what you are looking for.
https://www.partzilla.com/catalog/honda ... e/tubing-1
https://www.partzilla.com/catalog/honda ... e/tubing-2
https://www.partzilla.com/catalog/honda ... e/tubing-1
https://www.partzilla.com/catalog/honda ... e/tubing-2
- ct1500
- Posts: 1455
- Joined: Wed Nov 10, 2010 8:09 pm
- Location: Glastonbury,CT
- Motorcycle: 1988 GL1500
- Contact:
Re: Another full choke runner
Not a vacuum release. A carburetor controls RPM for a given load by the amount of throttle plate opening metering air/fuel mix into the engine. At a closed throttle idle an enrichment system needs to also add air to enable an increase in RPM.
The enrichment system adds fuel AND air via a dedicated carb circuit. The intake of this air is a port at the top of carb. The whoosh sound is simply the air making its way through this labyrinth into the engine and is normal.

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