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'84 CX650E that is evolving into a GL500
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It is normal to refer to the sides of a vehicle as left and right with respect to someone in the operator's position. This becomes more important when you are talking to people from other parts of the world; To most of us who have posted in this thread the "driver's side" of a car is the left but to CXphreak in Australia the driver sits on the right side of the car.

So you are referring to the left side of the bike.

And I had to look back to the first post in the thread to see which model you have (please remember to fill in your profile like I asked you to near the beginning of the thread).

The vacuum petcock your GL500 came with has 2 valves, a manually controlled valve that works the same as a non-vacuum petcock, allowing you to select between ON, OFF and REServe and a vacuum valve that prevents fuel from entering the manual valve when the engine is not running.

The carbs on these bikes have a tendency for the fuel in the float bowls to evaporate and fast enough that if they are not used for a week or so the level can get low enough that there isn't enough for the engine to start. The problem is that the vacuum petcock doesn't let any fuel into the carbs unless the engine is turning fast enough to produce vacuum so you have to crank the starter long enough for the engine to supply enough vacuum to the petcock to open the valve for a long enough time for the float bowls to re-fill and it is pretty easy to run the battery down doing that.

You have a few options when that happens:
  • If it has been sitting for a few days and you expect that it will be hard to start, before you touch the Start Button, vigorously whack the throttle open several times to operate the accelerator pump and squirt raw fuel into the carb throats.
  • If it has been sitting for a week or more (or the carbs were drained for storage or while working on them) and whacking the throttle doesn't help there are 3 ways to fill the bowls:
1) (preferred method) Disconnect the fuel line from the petcock, connect a funnel and pour 90cc of fuel in directly.
2) Disconnect the vacuum line from the petcock (this is the small barb farthest from the petcock's main body), connect a short piece of clean tubing in its place and apply vacuum (with a vacuum pump or just suck with your mouth) for about 10-15 seconds.
3) Disconnect the drain/vent line from the petcock (this is the small barb between the vacuum line and the main body), connect a short piece of clean tubing in its place and blow gently into it for 15-20 seconds.

Note that if the bike was sitting on the sidestand the left carb will be lower than the right one so as the fuel evaporates what is left will flow downhill to the left float bowl.
 

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Discussion Starter · #42 ·
It is normal to refer to the sides of a vehicle as left and right with respect to someone in the operator's position. This becomes more important when you are talking to people from other parts of the world; To most of us who have posted in this thread the "driver's side" of a car is the left but to CXphreak in Australia the driver sits on the right side of the car.

So you are referring to the left side of the bike.

And I had to look back to the first post in the thread to see which model you have (please remember to fill in your profile like I asked you to near the beginning of the thread).

The vacuum petcock your GL500 came with has 2 valves, a manually controlled valve that works the same as a non-vacuum petcock, allowing you to select between ON, OFF and REServe and a vacuum valve that prevents fuel from entering the manual valve when the engine is not running.

The carbs on these bikes have a tendency for the fuel in the float bowls to evaporate and fast enough that if they are not used for a week or so the level can get low enough that there isn't enough for the engine to start. The problem is that the vacuum petcock doesn't let any fuel into the carbs unless the engine is turning fast enough to produce vacuum so you have to crank the starter long enough for the engine to supply enough vacuum to the petcock to open the valve for a long enough time for the float bowls to re-fill and it is pretty easy to run the battery down doing that.

You have a few options when that happens:
  • If it has been sitting for a few days and you expect that it will be hard to start, before you touch the Start Button, vigorously whack the throttle open several times to operate the accelerator pump and squirt raw fuel into the carb throats.
  • If it has been sitting for a week or more (or the carbs were drained for storage or while working on them) and whacking the throttle doesn't help there are 3 ways to fill the bowls:
1) (preferred method) Disconnect the fuel line from the petcock, connect a funnel and pour 90cc of fuel in directly.
2) Disconnect the vacuum line from the petcock (this is the small barb farthest from the petcock's main body), connect a short piece of clean tubing in its place and apply vacuum (with a vacuum pump or just suck with your mouth) for about 10-15 seconds.
3) Disconnect the drain/vent line from the petcock (this is the small barb between the vacuum line and the main body), connect a short piece of clean tubing in its place and blow gently into it for 15-20 seconds.

Note that if the bike was sitting on the sidestand the left carb will be lower than the right one so as the fuel evaporates what is left will flow downhill to the left float bowl.
So I got it to fire up and idle for a few minutes. What I ended up doing was just tilting the bike over on the right side for a few seconds and it fired
 

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Discussion Starter · #43 ·
So I got it to fire up and idle for a few minutes. What I ended up doing was just tilting the bike over on the right side for a few seconds and it fired.
It fired up and ran for awhile. Only issue was that when I give it gas, it dies out. I just finished pulling the carbs apart and cleaning the pilots and main jets. Going to install carbs back on tomorrow and give it another shot.
 

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Discussion Starter · #45 ·
How much gas was there in the float bowls? If they hadn't finished filling yet that could account for it stalling when you gave it throttle.
That’s what I think it may be. So tomorrow when I get everything back together I’m going to just let it idle for awhile so the fuel can fill up the bowls. Hoping I can get this thing going soon so I can actually start building it.
 

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'84 CX650E that is evolving into a GL500
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They should fill pretty quickly once the engine is running but if you emptied the bowls when you had them apart I would advise connecting a funnel to the fuel line that goes to the petcock and pouring 90cc of fuel into the bowls before you try to start it.
 

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Discussion Starter · #47 ·
They should fill pretty quickly once the engine is running but if you emptied the bowls when you had them apart I would advise connecting a funnel to the fuel line that goes to the petcock and pouring 90cc of fuel into the bowls before you try to start it.
I will do that before as well then
 

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Discussion Starter · #48 ·
I will do that before as well then
So now it fires up perfectly with everything on. Just have an idle issue, going to try to adjust my cables first. If that doesn’t work going to adjust the idle control knob on the carb.
 
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