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Discussion Starter #1
According to the owners manual for my bike it say's to turn the petrol tap to off when the bike is left standing, Is this neccesary. I thought the petrol was pulled through by a vacum caused from the engine running..??????
 

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i thought they were on all hondas anymore. however older bikes, the petrol could leak out because they were gravity fed.

when i had a petcock, i always turned it off.
 

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Mine has a petcock, but I NEVER turn it off. I've never had a problem. Well when I'm trucking her somewhere I turn it off, but that's the only time.
 
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Here's some posts from an old thread that might be helpful...

On my Kawasaki Concourse (yea I know, but I got better and bought a Suzuki ) it was something I did because the Concourse had a habit of letting fuel continues to flow. There were many reports of people going to start their bikes and hydraulicing the engine (gas don't compress too well). But on a bike with a fuel pump I don't think it would be much of a problem.

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In the olden' days, bikes had just one line coming out of the petcock, the fuel line. If you didn't shut the line off while sitting - gravity would draw the fuel slowly down into the motor. I never heard of them hyrdaulocking but I have heard reports of Explosions before. What the manufacturers did the was to put a vacuum line from the carbs or the intake into the petcock along with the fuel line. The vacuum line opens up a valve that alows the fuel to pass through when the engine is turning, so on these models there is no need to shut the petcock off.

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I never heard of them hyrdaulocking but I have heard reports of Explosions before. What the manufacturers did the was to put a vacuum line from the carbs or the intake into the petcock along with the fuel line. The vacuum line opens up a valve that alows the fuel to pass through what the engine is turning, so on these models there is no need to shut the petcock off.

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The Concourse has a 7 gal tank and if you can easily fill the crankcase and with gas. From what I understood was the diaphragm in the petcocks were weak and would stay open allowing the fuel to flow and because of the way the carbs sat this allowed the fuel to flow right into the intake. I got this info from the COG site when I use to own that bike.
 

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"bladerunner" said:


5 mins are you sure ????? :confused: :confused:
Not sure on the timing, but in my MSF course, they had us turn the things off every time we left the bikes standing. I think you're safe if you take the bike on a brief jaunt to the grocery store or something, but I would probably turn it off if I took it to a movie. I'd probably also turn it off (if my bike had one) when I went to hang out at the local hangouts too.
 

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I think the reason that they teach that during MSF is security, the theory being that if you turn off the fuel tap and the kill switch, then those are two sort of "idiot proof" (or idiot prone) ways of fooling a potential thief -- they have to think to look and flick the kill switch, and then if they don't catch the petcock, they run out of gas in ten feet, and you catch them, ha ha!

That was also, as I remember, the reason given in teh owner's manual for my 93 CBR6 -- not because of a fuel leakage issue.

On the other hand, long term storage involved turning off the fuel tap, but that was to make sure the carbs ran and stayed completely dry, and therefore wouldn't have to be cleaned in the Spring (nasty job...:barf: )
 

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Leave the kill switch off too?

Not only they teach you to turn off the fuel at petcock at MSF classes, they also instruct you to shut the ignition switch.

However, my manual says to always leave the ignition switch on (F4i). So, who is right?

Don't you guys always leave the ign. switch in "on" position even overnight?
 

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Discussion Starter #10
Re: Leave the kill switch off too?

SpeedRacerF4i said:
Not only they teach you to turn off the fuel at petcock at MSF classes, they also instruct you to shut the ignition switch.

However, my manual says to always leave the ignition switch on (F4i). So, who is right?

Don't you guys always leave the ign. switch in "on" position even overnight?
I leave the ignition switch always and i never turn the petrol tap off either, The only time i've turned the tap off is when i've taken the tank off for some reason and i can't remember ever having any problems with leaving the fuel tap on even when i've left the bike for 6 or 7 weeks without running it......
 

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I shut off the engine everytime with the kill switch. Bad habit...? Don't know but because I do I always just flip it on before I start it without thinking. Never been a problem. As for the valve, even my old '81 CB750 didn't need it closed when it sat around.
 

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It's good to use the petcock every now & then because if you just leave it in one position, the "rubber" inside dry rots, and then the petcock starts leaking out of the switch face. Nimbus, not a good idea to use the kill switch all of the time because it's a low-cost switch, with a much shorter service life than the ignition switch.
 
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