Not startng for seemingly no reason

[JaNewb]

His petcock looks like it's the same as my '80 1100E... I bought a Pingel PN# 18-7167 and an adapter plate to go with it. I believe mine measured 50 mm c-c. Want me to verify?

If ya could point me in the right direction to what you got I'd be much obliged.

[tom203]

Yep I just measured it and I'm not sure about the year but it's a leverless petcock, 50mm bolt spacing. As far as I can tell it has a working vacuum line that is functioning.

Some 1981 gs750s came with the leverless petcock and some had a lever type
Anyway, the leverless petcock has some odd operating functions, especially at getting fuel to flow- maybe the cold has made its vacuum diaphragm sticky.

[Gorminrider]

Naw no maintenance at all. Nothing done to it other then the temp dropping 10-20 degrees. That's why I was confused as to how it roars to life one day and sputters out a couple days later. The only thing that changed was the temp. It worked just fine before, no reving at lights to keep the rpms up or holding the starter very long before it starts. It'd turn over like once and fire right up. Was steve's thread about something similiar?

jaNewb, Steve's post here... on bluehwy's thread:

http://www.thegsresources.com/_forum/showpost.php?p=1792157&postcount=17

I had hopes for that to fix it!

I had a similar issue exact to yours a few weeks ago on my GSX400TX. It too starts great no issues whatsoever. But, that day, No start, no good reason except it was two weeks into our winter...What-the-heck! Pulled the plugs, checked the bowls for gas.Something I didn't like about the smell of that gas at that station at that time I bought it...I had put Stabil in it in the fall,too.
Drained the carb bowls, and TANK too-put fresh gas in, turn gas valve to Prime let sit to fill bowls. Choke, Started!
Did I really fix it? Maybe, but sometimes I think an engine just wants a massage.
...the old gas works ok in the car as partial tank...maybe it's" summer gas"maybe it was just nasty when I bought it.

[JaNewb]

Some 1981 gs750s came with the leverless petcock and some had a lever type
Anyway, the leverless petcock has some odd operating functions, especially at getting fuel to flow- maybe the cold has made its vacuum diaphragm sticky.

But it shouldn't be a problem to switch it out right? I don't like the fact that I can't turn it off. It makes me worried there is a possible leak or something and flooding my engine. Ah and the thing about the cold is that as an experiment I put oil pan heaters and an electric blanket over it then another cover over it to keep the heat in. Even though it was warmer in there it didn't help.

[JaNewb]

jaNewb, Steve's post here... on bluehwy's thread:

http://www.thegsresources.com/_forum/showpost.php?p=1792157&postcount=17

I had hopes for that to fix it!

I had a similar issue exact to yours a few weeks ago on my GSX400TX. It too starts great no issues whatsoever. But, that day, No start, no good reason except it was two weeks into our winter...What-the-heck! Pulled the plugs, checked the bowls for gas.Something I didn't like about the smell of that gas at that station at that time I bought it...I had put Stabil in it in the fall,too.
Drained the carb bowls, and TANK too-put fresh gas in, turn gas valve to Prime let sit to fill bowls. Choke, Started!
Did I really fix it? Maybe, but sometimes I think an engine just wants a massage.
...the old gas works ok in the car as partial tank...maybe it's" summer gas"maybe it was just nasty when I bought it.

Ya this happened once before and it just took a little coaxing to get her up again. Did the same thing I did last time but it didn't work this time.