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Main Area => General GS500 Discussion => Topic started by: GI JOE on May 14, 2013, 02:41:57 PM

Title: fuel lines too long???
Post by: GI JOE on May 14, 2013, 02:41:57 PM
Hey all, I was riding around today and got fuel starved twice. It happened a lil after going a bit hard on her, as in fast. Now I cleaned my carbs thoroughly and used a rebuild kit recently, so I know my jets are clear. But I had to replace the fuel lines, the DS that owned it before me used vacuum lines. So it's got the ordinary car fuel hoses as thick in diameter as the nipples, but the have some sag to them.

Would the sag mean my lines are too long and not letting the bowls fill right?

After I realized the starvation I pulled off and put her on prime and she ran fine so I kept it on that to get home.

I appreciate any ideas on how to solve my issue.
Title: Re: fuel lines too long???
Post by: adidasguy on May 14, 2013, 04:23:53 PM
Long lines are not a problem.
Prime is same as being in reserve except the vacuum is bypassed.
Were you low on gas?

Also, somewhere else I posted a quite from the Haynes Motorcycle Fuel System book. It explains that if you do things like rejetting and changing air filters from factory, you can cause issues due to too high fuel demand and possibly low vacuum for the fuel petcock.

You might check the routing of your vacuum line from the carb to the petcock. also an occasional cleaning of the petcock can make a difference. They can get filled with gunk just like the carbs and tank if gas sits there for a long time (like over the winter).
Title: Re: fuel lines too long???
Post by: GI JOE on May 14, 2013, 04:45:56 PM
No rejetting, one pilot is stripped out in the carb, you don't wanna know how I rigged something up to clean that jet.. So it's all stock. And it's a full tank of gas in there. All hoses are set like the diagram I've seen on the wiki.

I'd assume the petcock now from what you're saying. Is it easy to clean that and fast?
Title: Re: fuel lines too long???
Post by: adidasguy on May 14, 2013, 05:05:21 PM
Watch how you take it apart. Pop the clip off and like 4 parts are there. Clean them and clean all the ports then reassemble.
Pay attention to the valve orientation as well as the lever and retaining clip.

I cleaned one out that was full of goo. It made a difference.

If you never put your bike on reserve, the reserve line can have gas years old. Same as if you only run on reserve - the main line can have ancient gas.
I try to run on reserve for a mile or so after a fill up every couple full ups so the lines are always filled with clean gas.
....and that old has sitting there can get gooey crap. When you do switch, now you have ancient gas from the reserve line now gumming up everythig.

Look at the pictures of the gas lines in the thread about the rebuilding of Quin. Like molasses in the fuel lines. Same as the petcock. It got cleaned out.
Title: Re: fuel lines too long???
Post by: GI JOE on May 14, 2013, 06:30:20 PM
Ok cool thanks for the tips. I'm considering buying one to clean up and swap out so I can keep riding for now but may just take her out of commission for a day. I appreciate the help, hope it solves my issue.
Title: Re: fuel lines too long???
Post by: Zwerski on May 15, 2013, 09:16:34 AM
I'm planning on replacing the fuel lines, vacuum lines and petcock soon. One thing I have been thinking about is making the lines longer to possibly help with tank removal for maintenance. However, I am sure there is a sweet spot for line length between the minimal stock length and some extended length. I can see how having too much fuel line can lead to the lines piling up and getting kinks more easily than stock length. I'm thinking a max of 3-4 inches more than stock would be it.
Title: Re: fuel lines too long???
Post by: GI JOE on May 15, 2013, 09:33:18 AM
That's what I did with my lines, a little longer to make work easier. Not enough to kink but like I said I have som sag in them.
Title: Re: fuel lines too long???
Post by: adidasguy on May 15, 2013, 09:44:00 AM
I always make fuel lines longer. No effect other than easier to work on.
See? Here is Quin after new fuel lines.
(http://www.gs500.net/gallery/data/2/IMAG0085a.jpg) (http://www.gs500.net/gallery/showphoto.php/photo/241/title/imag0085a/cat/2)
Title: Re: fuel lines too long???
Post by: BockinBboy on May 15, 2013, 12:30:49 PM
..Just don't get them so long that they touch the engine   :icon_eek:  ...  You still want them to fit into that small crossbar space behind where the frame angles, and not below that crossbar for this reason.  Longer lines aren't a big deal otherwise with a vacuum operated petcock  :thumb:

- Bboy