reason behind turning the fuel petcock off?

Discussion in 'Motorized Bicycle General Discussion' started by dumpstercrusher, Jul 27, 2013.

  1. dumpstercrusher

    dumpstercrusher New Member

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    why does everyone say that you should turn the fuel petcock to the off position when you park the bike? or even when u know ur not going to ride it for a week or so?
     
  2. fatdaddy

    fatdaddy New Member

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    Because, if for some reason your float sticks open it will stop fuel from pouring all over your garage floor. OR ANY leak that may happen after the petcock.
    Just a little peice of garbage stuck in the float needle will let fuel overflow. It happens all the time.
    fatdaddy.
     
  3. bairdco

    bairdco a guy who makes cool bikes

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    also, the weight of the fuel can overpower the float and cause it to fill up the engine, spill out the catb, and make a huge mess.

    and honestly, there's no good reason why you should leave the fuel on whenever the bike's off. it took you longer to type this question than it takes to twist a little handle.
     
  4. tooljunkie

    tooljunkie Member

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    my tank emptied while sitting parked for an extended period.
    i make it a habit to shut fuel off while its running and empty the bowl a little,this way next time i run it i know the needle valve in carb isnt stuck closed.which is a common thing with todays poor excuse for gasoline.
     
  5. crassius

    crassius Well-Known Member

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    most often, the angle it sits at on the kickstand will let the float open the needle and fill your whole bottom end with fuel
     
  6. mapbike

    mapbike Active Member

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    Lol..... amen to that bro.
     
  7. mapbike

    mapbike Active Member

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    Forgot to turnnit off on one of mine one time and yepnext day engine completely full and draining out exhaustpipe under bike in shop...... I saw it and knew exactly what I had done , pulled tje sprk plug turned entire bike upside down and finally got all tje fuel out, that probably cost me about $4.00 in gas and Opti2......!
    So simple and so quick.....just turn the fuel off and back on when you're ready to ride.....
     
  8. 2door

    2door Moderator
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    There's a reason they put a petcock in the kits. If they didn't think it was necessary, believe me, they wouldn't include them. Install and use it.

    Tom
     
  9. bigbutterbean

    bigbutterbean New Member

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    With 2 strokes, the worst that happens is the engine floods and gas gets everywhere (bad enough in itself, don't get me wrong). But you let the spark plug dry out, clean the mess up, and eventually the engine will start again just fine once all the fuel is out of the engine, as long as there is fresh gas in the tank. On the subject of petcocks, the carb petcock by itself is not enough to stop fuel from leaking out of the tank. I've had fuel leaks with the tank petcock open and the carb petcock shut. Its best to either use the tank petcock or an inline fuel valve. If the one that comes with the kit works, use it. If not, you can go to just about any hardware store and get a threaded nipple and a ball valve. Screw the threaded nipple on or into the tank threads, attach a small section of fuel line, then install the ball valve and connect the other end of the fuel line to the carb. I have done this and its worked good for me. Now onto the subject of 4 strokes. If you dont properly shut off your fuel on a 4 stroke, straight gas can leak into the crankcase and thin out your oil, which is a little worse than dealing with flooding on a two stroke. I believe that gas leaking into the crankcase is responsible for the failure of more than one 4 stroke engine on this forum. As it happens, I've got a petcock on my tank and my carb, and I use them both. In fact, I crashed about a month ago and my carb petcock lever snapped off in the open position. I could have left it that way and just used the tank petcock, but I was concerned that even the tiny amount of fuel in the line could seep into the crankcase. So I found a replacement fuel shutoff lever as quickly as I could. I feel much more comfortable knowing that with both petcocks shut that there is almost zero chance of fuel seeping into my crankcase.
     
  10. xseler

    xseler Well-Known Member

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    Well, I keep my bike in the garage fairly close to the water heater............spilled fuel with the accompanying vapors would be very bad mojo.
     
  11. Allen_Wrench

    Allen_Wrench Resident Mad Scientist

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    When the cheapa$$ petcock that they provide with the kits goes bad, you'll know why it's there. Trust me. If (or when) it works correctly, then using it can save a lot of headaches, like an engine full of gas and gas all over the floor, etc.
    The glass bowl fuel filter I have now has a petcock built in. And it works so perfectly. On most cases the kit ones are okay, but now and then you get a lemon. Let us spare you the trouble of learning the hard way: let us advise you to turn off the petcock when not in use. You'll be happier.
     
  12. Trey

    Trey $50 Cruiser

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    Crusher- The only bad question is the one you don't ask. You have been well answered here.
    Keep tinkering, and good luck! (^)
     
  13. dumpstercrusher

    dumpstercrusher New Member

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    Thanks for all the answers lol
     
  14. Dan

    Dan Staff
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    ...I need a devise to remind me to turn the thing back on.

    So dang embarrassing. No matter which motorized bicycle I am on, they seem to sputter out in front of the same neighbor's house. Great guy and one night he scraped me and my bike off the road. I bled all over his cab and the bike leaked gas all over the bed of his truck.

    Good times, snork.
     
  15. dodge dude94

    dodge dude94 New Member

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    I turn the petcock on before I even pull the bike out of storage. lol
    I have left it on before and never had issues with fuel pouring out of the carb, but I also had little fuel in the tank. But I use it anyhow. Like one of the others said, if it wasn't necessary, China wouldn't have included it.
     
  16. Master-shake

    Master-shake New Member

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    I put an inline fuel filter on my last bike and it never leaked. I never used the petcock. The only time I ever used it I forgot to turn it back on and started going home. I was almost half way back home before the engine finally ran out of gas.
     
  17. 2door

    2door Moderator
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    Don't feel bad, Shake. If the truth be known I'd wager that the majority of us have forgotten to turn the fuel on AT LEAST ONCE :)

    The embarrassment comes when you're setting on the side of the road trying to figure out why the engine shut down. Actually I think there is an old thread about it here somewhere.

    Tom
     
  18. Dan

    Dan Staff
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    LOL Tom, was it the "dumb stuff I done did"? or some thing like that, thread? I have been looking for that one. 2 dang funny.
     
  19. allen standley

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    My latest build- Let my friend run it for a couple days to assist break-in. Yup he did not shut off the fuel 2nd night and discovered gas all over his garage floor the nxt morn. Case was full and clutch pads were soaked. I got about 6 hrs into cleaning it up, now I got clutch issues. I'm so mad at him I can't even look at it. Bike hasn't been right since. that was last week. Big trouble to avoided if you will please shut fuel off when parked. Shut the D*** fuel off and stop leaving my battery powered lights on when parked idiot!

    I did print some stickers for the mirror that remind people to shut fuel and flashers off. No No it never happened to me.
     
  20. Allen_Wrench

    Allen_Wrench Resident Mad Scientist

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    And I'd wager there's a few of us who, even if we knew how often it happened to us, would be too embarrassed to say.:-||
     

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