Hello friends,

My 1991 GS500E again has the dreaded frame petcock fuel starvation problem.
I know, our good friend Patrick, said it was all in our heads, but hey, I'm having this happen a second time. 
The first time I replaced the original OEM petcock with a brand new one about 14 years ago.

Now I'm thinking about...

1) replacing it with yet another OEM stock petcock (this idea does NOT thrill me).

2)  doing the JB Weld mod on the original petcock, so I fill in several passages with JB Weld and convert it into a NON-VACUUM petcock for almost nothing. 
I like this idea but in the years since someone else on the board proposed this fix (Jenya), others have voiced concerns about ethanol and its effects on the JB Weld over time.

3) Then there is the idea of replacing the whole damned stupid OEM petcock with the alternative from a 2004-07 Honda CRF250X, which fits with minimal mods.

Now I ask you, I'd love to hear your opinions on this, especially GSJack, Buddha and Sledge, who are some of the longest-tenured GS500 owners in our community.

The OEM unit will fail again in 10 or so years.

The JB Weld mod is worth trying if the ethanol won't dissolve it and cause other issues in the future.

And the Honda petcock would be fine except that means running a longer fuel line to the carbs and that means a big fuel hose bend at the rear of the Honda petcock (is there room for this back there?) and it also requires pulling the carbs to replace the fuel line to the carbs (located at the bottom center of the carbs where it is a pain to reach with them on the bike). I'd rather not do that until its no longer riding season here in PA. 

Anyone done the JB Weld trick and not had problems?

Thanks for your thoughts and Happy Father's Day to all of you dad-like GS500 owners out there.

Yours,
Trwhouse 

You sure your gas cap vent isn't clogged?

While I dont know a thing about turning a vacuum petcock into a non-vacuum, I must recommend the harbor freight two part epoxy for use in gasoline saturated applications. My father first tested it for waterproofing homemade 50 gallon drum lids, and later used it to seal pool filter fittings. I supposed that if it could handle chlorine it could handle fuel, so I tested a cured batch in gas over a few days, and it showed no signs of pouring or cracking. I then used it to secure a broken off float mount on a 1981 xs650 carb, with a steel dowel for strength. Its been atleast 6 years since that repair, and although we have not taken the carb apart since then, the bike doesnt flood or go lean. This is only my experience however, using it as pretty much a butt joint glue, and theres no telling if it would work as an orfice block as I suspect you intend to do.

You could have a clogged upper petcock, and even the frame petcock can crap out that way, hey, nothing is immune to crapping out.
Is the vacuum part causing you trouble ? As in - is prime better than on/res Then you could probably put a new diaphragm in that section and hope that fixes it.
Cool.
Buddha.