Announcement

Collapse
No announcement yet.

petcock differences

Collapse
X
Collapse
 
  • Page of 1
  • Filter
  • Time
  • Show
Clear All
new posts
Previous template Next
    #1

    petcock differences

    what makes a vacumn operated petcock turned to the prime setting (like what is on my gs750 81) different from a petcock with no prime, no vent tube thingy , no reserve (which i don't have anyway!) but just has an on/off lever? seems like the on position would be the same as the prime postion on the stock petcock. :? i found a REALLY nice tank but it only has a petcock with an on/off lever. i know i will have to close off the vent tube that goes to the carbs, and should turn the lever to off each time i stop, :? but is there anything else i should be aware of? thanks! sorry this is so long!
    Tags: None
    #2
    You have to manually turn a vacuum operated petcock to prime. It's only in vacuum mode when it's either at on or reserve. I have a non vacuum pingel and it has on/off/reserve. The on position is the same as prime and it's always a good idea to turn it off when you're not riding.

    I would remove the vacuum tube altogether and cap the vacuum port on the carb. You can usually find little rubber vacuum caps at any automotive store.

    Comment

      #3
      No nothing else Sue Ann from what I understand. Haven't done it myself but have read multiple posts on here about it and your right on track. Just always remember to turn it off when you shut off the bike and to turn it on when you go to start it. That appears to be the only down side of doing it this way.

      Comment

        #4
        Re: petcock differences

        The on/off petcock will work just fine. The first thing I do with any bike I get is remove the vacuum petcock and throw it as far as I can. :-) The only down side to a manual on/off petcock is that you must remember to turn it off when you shut the engine down. Otherwise, if your carb float needles seep any at all, you run a good chance of having gas drain into your crankcase oil. (which is exactly the problem you have with a faulty diaphram on a vacuum petcock)

        Just remember to turn it off and all is well. You wont forget more than a couple of times, when you have to keep changing the oil because you forgot. :-)

        Earl


        Originally posted by Sue Ann
        what makes a vacumn operated petcock turned to the prime setting (like what is on my gs750 81) different from a petcock with no prime, no vent tube thingy , no reserve (which i don't have anyway!) but just has an on/off lever? seems like the on position would be the same as the prime postion on the stock petcock. :? i found a REALLY nice tank but it only has a petcock with an on/off lever. i know i will have to close off the vent tube that goes to the carbs, and should turn the lever to off each time i stop, :? but is there anything else i should be aware of? thanks! sorry this is so long!
        Komorebi-The light filtering through the trees.

        I would rather sit on a pumpkin and have it all to myself than be crowded on a velvet cushion. H.D.T.

        Comment

          #5
          thanks for the replies!

          when i first got this bike and before i figured out what "prime" was i gave my old engine a few gasoline baths. "hey hey why's the thing running so rich?" and "whats all that white smoke and why do i smell gas?" and " how come the sight window is SO full?" duh. took me twice to figure it out. now i understand the petcock stuff more than ever. i will go ahead and purchase the tank (very nice and no dents) -- and hopefully i'll remember to turn the valve off. if not, i will at least after two more times!

          so there is no difference in fuel flow rate amongst the petcocks? hhm.

          this list is great!

          Comment

            #6
            Usually, the flow rate of a manual petcock is a bit better than the stock vacuum ones and in the case of a Pingel manual petcock, it is a LOT better.

            Earl

            Originally posted by Sue Ann
            so there is no difference in fuel flow rate amongst the petcocks? hhm.

            this list is great!
            Komorebi-The light filtering through the trees.

            I would rather sit on a pumpkin and have it all to myself than be crowded on a velvet cushion. H.D.T.

            Comment

              #7
              My experince may be different, but I am still running the original percock on my 78 GS1000, which is vacuum operated. I have never rebuilt it, never had a problem. I can't see why so many people worry about it and want to replace it..is it something in the Northern hemisphere? Does the petrol go in a different direction into the tap? Are 4 valves really necessary?

              So many questions...

              Comment

                #8
                Originally posted by saaz
                My experience may be different, but I am still running the original percock on my 78 GS1000, which is vacuum operated. I have never rebuilt it, never had a problem. I can't see why so many people worry about it and want to replace it..is it something in the Northern hemisphere? Does the petrol go in a different direction into the tap? Are 4 valves really necessary?

                So many questions...
                Nope, nothing to do with the location saaz My experience mirrors yours. My petcock is 27 years old, never been rebuilt and works like the day it was new. This is also the case for every other motorcycle I have owned with vacuum petcocks. Which has been all of them. That's not to say others haven't had issues because obviously they have. But I am like you and have never had an issue with it. <knocking on wood>

                Comment

                Previous template Next
                Working...
                X