I think you may be able to rebuild the petcock, but if not you have to replace it.

 

well a new petcock costs 220+ OEM from the local shop. soo before i sell a kidney to get my bike running, i am going to look into the petcock i have, which appears to be fine after taking it apart.

after doing some research, i realize i had a misconception on how this works. when i blow into it there really shouldnt be any air throughput. there is a vacuum tube that pulls the membrane that then compresses the spring allowing gas through, so the fact that gas didnt come out of the tank when i unhooked it means the petcock is functional.

this means that either there is no gas getting to the petcock, via hoses/screens... or there is not a correct seal between the petcock and the vacuum tube. orr the lines leaving the petcock... but idk

any guesses?

also, where are these "screens"? i cant seem to locate them. my guess is clogging somewhere.


i ordered a new O ring which is a part on the petcock because it was only 3 dollars and you never know... it could help.


slightly confused... fundamentally, there is no gas getting to the engine. (from what i can tell.) so from the tank to the engine we have?
-gas lines/screens
-petcock (and vacuum tube)
-gas lines leaving petcock
-carbs

am i missing anything?

im afraid if i buy a new petcock and still have this issue i might injure myself. i am basically looking for a way to prove that the petcock is the culprit...

 

You can actually test the petcock by sucking air from the vaccum line...this should allow fuel to flow. It would be VERY bad if fuel flowed without the suction on the vaccum assist....then your carbs would fill up with fuel. There is only the one screen in the tank and it's hardly enough to catch unwanted debris...nevermind blocking the fuel system. Have you checked all fuel lines to the carbs, the main fuel line goes to a t and splits into two lines. There are a million tests you can do to see where the fuel stops...especially if you have it apart already.

 

thank you all for your help.

so i cleaned out the carbs which incedentally had lumps of s*** in them. also replaced the plugs, charged the battery. got it to start and it was running good. i took it to work the next day and everything was good but then i hopped on it the day after and a mile later it started to cut out the same way it did the first time. by this time i was sooo confused as to what it could be.


turns out that this whole time it was bad gas!! there was an inch of sediment in my tank which i was certain wasnt there before the last time i had filled up. soo i drained the tank and carbs etc, put new gas in, and havent had a problem since. fired up and running great. ill get a fuel filter asap

thanks to everyone for your suggestions