RE: 1980 GS 1100 16 vakve Carbs Leaking out vent tubes

[mrbill5491]

I have a Pingel on mine, you just need the adaptor plate for it

Won't work on his bike, no room for a Pingel with an adaptor plate. He would have to raise the tank quite a bit to make it work, then that is gonna cause some problems. Telling ya, it's tight fit right there.

[KatManDo]

Thanks for the great info. Good to know. Can these bikes be converted to a normal On / Off petcock using the BS34 carbs?

Hey Chewbacca5000, was just reading through this post and although I see that you edited it about a week ago and have now fixed your problem I thought I'd answer one of your questions regarding converting the petcock to a simple ON/OFF device. The answer is "yes" you can. I just did this very job to the petcock on my 1000 Kat. You will need to completely dismantle the petcock. The 4 screws on the back where the vacuum line is will need to be removed to access the diaphragm and shut-off plunger. Remove the complete innards and replace the cover making sure you seal it against fuel leakage by applying a good quality fuel resistant sealer. Next, find a way to plug the vacuum connector on the petcock. I tapped with a M5 tap and put a very short machine screw inside with some sealer. I can now attach the vacuum line from the carbs and not negatively affect how they work. Next remove the actual petcock lever by un-clipping the metal retaining cover ( the one that says ON/RES/Prime) and then pull out the plastic fuel diverter. There are two holes in it. One that selects ON or RES depending on the lever position and the other hole at 180 deg is for the prime. (FYI, the prime position does not need a vacuum to operate. The whole point is to fill the bowls before hitting the starter button ). Behind the diverter is a brass coiled actuator. Pull it out with needle nose pliers and chuck it in the bin. The object here is to turn the PRIME position into an OFF position. Therefore you need to find a way to block off that hole. I used my M5 tap and threaded the hole and screwed in another M5 machine screw. Very short of course, and once in position gently shaped any protrusions with a fine file to match exactly the contour of the conical profile of the diverter. Once I was happy I refitted everything, tried it out to ensure smooth operation and that the there were no leaks through my blocked off hole and hey presto one ON/RES/OFF petcock. Works like a charm and all I need do now is to remember to turn the fuel off at the end of the day's ride. Simple and effective.

[Spyderman]

Hey Chewbacca5000, was just reading through this post and although I see that you edited it about a week ago and have now fixed your problem I thought I'd answer one of your questions regarding converting the petcock to a simple ON/OFF device. The answer is "yes" you can. I just did this very job to the petcock on my 1000 Kat. You will need to completely dismantle the petcock. The 4 screws on the back where the vacuum line is will need to be removed to access the diaphragm and shut-off plunger. Remove the complete innards and replace the cover making sure you seal it against fuel leakage by applying a good quality fuel resistant sealer. Next, find a way to plug the vacuum connector on the petcock. I tapped with a M5 tap and put a very short machine screw inside with some sealer. I can now attach the vacuum line from the carbs and not negatively affect how they work. Next remove the actual petcock lever by un-clipping the metal retaining cover ( the one that says ON/RES/Prime) and then pull out the plastic fuel diverter. There are two holes in it. One that selects ON or RES depending on the lever position and the other hole at 180 deg is for the prime. (FYI, the prime position does not need a vacuum to operate. The whole point is to fill the bowls before hitting the starter button ). Behind the diverter is a brass coiled actuator. Pull it out with needle nose pliers and chuck it in the bin. The object here is to turn the PRIME position into an OFF position. Therefore you need to find a way to block off that hole. I used my M5 tap and threaded the hole and screwed in another M5 machine screw. Very short of course, and once in position gently shaped any protrusions with a fine file to match exactly the contour of the conical profile of the diverter. Once I was happy I refitted everything, tried it out to ensure smooth operation and that the there were no leaks through my blocked off hole and hey presto one ON/RES/OFF petcock. Works like a charm and all I need do now is to remember to turn the fuel off at the end of the day's ride. Simple and effective.

pictures of how you did this along with a detailed set of instructions (like the carb cleaning tutorial)
would be a good thing to do so that others can do this if they want

[mrbill5491]

Hey Chewbacca5000, was just reading through this post and although I see that you edited it about a week ago and have now fixed your problem I thought I'd answer one of your questions regarding converting the petcock to a simple ON/OFF device. The answer is "yes" you can. I just did this very job to the petcock on my 1000 Kat. You will need to completely dismantle the petcock. The 4 screws on the back where the vacuum line is will need to be removed to access the diaphragm and shut-off plunger. Remove the complete innards and replace the cover making sure you seal it against fuel leakage by applying a good quality fuel resistant sealer. Next, find a way to plug the vacuum connector on the petcock. I tapped with a M5 tap and put a very short machine screw inside with some sealer. I can now attach the vacuum line from the carbs and not negatively affect how they work. Next remove the actual petcock lever by un-clipping the metal retaining cover ( the one that says ON/RES/Prime) and then pull out the plastic fuel diverter. There are two holes in it. One that selects ON or RES depending on the lever position and the other hole at 180 deg is for the prime. (FYI, the prime position does not need a vacuum to operate. The whole point is to fill the bowls before hitting the starter button ). Behind the diverter is a brass coiled actuator. Pull it out with needle nose pliers and chuck it in the bin. The object here is to turn the PRIME position into an OFF position. Therefore you need to find a way to block off that hole. I used my M5 tap and threaded the hole and screwed in another M5 machine screw. Very short of course, and once in position gently shaped any protrusions with a fine file to match exactly the contour of the conical profile of the diverter. Once I was happy I refitted everything, tried it out to ensure smooth operation and that the there were no leaks through my blocked off hole and hey presto one ON/RES/OFF petcock. Works like a charm and all I need do now is to remember to turn the fuel off at the end of the day's ride. Simple and effective.

His petcock is different then yours. Look at the parts fiche, his petcock is #1 unit(no lever). not the #3(with lever) they also show of which I do not know why and for some odd reason for the 81 GS1100E the only show the #3. There is no difference between the 80 and 81 models. Same thing for the 750E. I've tried fitting the #3 once no go. So, not sure your conversion would work for him.

[KatManDo]

His petcock is different then yours. Look at the parts fiche, his petcock is #1 unit(no lever). not the #3(with lever) they also show of which I do not know why and for some odd reason for the 81 GS1100E the only show the #3. There is no difference between the 80 and 81 models. Same thing for the 750E. I've tried fitting the #3 once no go. So, not sure your conversion would work for him.

Oops !! and there I was thinking I was going to blind everyone with my knowledge

Thanks for pointing out my error. For those of us with the kind of petcock I was describing (the one with the lever) doing this conversion is easy and very effective. I hope at least a few people will benefit from my enthusiasm to shine !!

Great site. A pleasure to be part of the community

[KatManDo]

pictures of how you did this along with a detailed set of instructions (like the carb cleaning tutorial)
would be a good thing to do so that others can do this if they want

You're right Spyderman. I was thinking of that when I first replied to the thread but thought my simple explanation would suffice. I will go and remove the petcock before I fill the tank and take some pics.

[chewbacca5000]

Thanks KatManDo,

When I posted this I did not understand how the vac pet works specifically the prime position. I had it in prime when I thought I was in normal mode and the fuel would not shut off. I am used to manual petcocks from my experience with the CBs. So long as the vac works I can deal with it. If it fails I will go manual.