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Discussion Starter #1
My bike doesn't have the prime option on the ignition (CBR F3) and I don't want to burn up the starter waiting for the float bowls to fill (installing a jet kit).

Can I just connect some wire to the pump and it will fill the carbs to the proper level or will it overfill them? (I don't really understand how carbs work in this manner, i'm used to the systems that return excess fuel to the tank)

Thanks.

Ohh I really don't want to pull the bike behind a car to prime the system either.
 

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Discussion Starter #3
Are you sure? When I have the bike running you can feel the pump pulsing, when the ignition is in the on position but not running I can't feel it doing anything. Whats the point of a prime position on electric fuel pump bikes then?
 

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I didn't think there was a fuel pump on a carburated bike. mmmmmm. I thought the fuel was sucked out of the tank thru engine vaccum. Am I wrong?
 

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Discussion Starter #5
I am positive there is one on my F3, and it feeds directly to the carbs. I know some carbs don't use electric pumps, but am foggy on the details
 

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DT is happy it snowed
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Yea, if your bike has a fuel pump, the pump should prime the carbs when the key is switched to the "on" position without needing to crank the bike. However since the tank is still located above the carbs, gravity should still do its job if you let the bike sit for a bit with the petcock allowing the fuel through. If you are really concerned about making sure there is fuel available after letting fuel flow in for a bit, you can slightly open the drain bolts on the float bowls. Make sure gas comes out. Then you know your good to go. You really shouldn't have to worry about burning out the starter as long as your not using it for a minute at a time or so however. I really wouldn't give this too much thought, you should be just fine going about buisness as normal when you start it up.
 

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Some carbed bikes have fuel pumps to maintain pressure, but it is more unusual. FI bikes use a much higher fuel pressure and all require pumps.

Remember, the pump is hot all the time, not just on starting. But it takes a second to pressure up and won't necessarily pump unless fuel pressure requires it (depending on the system.) Return systems pump constantly and regulate pressure on the return. Returnless systems on newer bikes and cars forgo the return system and maintain pressure electronically. It's an emissions related change.

It's simply not something you need to worry about.
 

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VTX1300c rider
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I don't think you will damage your starter its not that fragile, the float bowls are small and don't hold a lot of gas even it is a gravity feed they won't that long to fill, It would be the same as draining them before you store it for the winter
 

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Go #214!!!!!!!!!!!!!!!!!!
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Don't you think if it was a necessary feature on the bike the manufacturer would have included it when they built it?
 

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at the track
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Your bike is gravity fed there bud. As long as the gas is above the petcock there will be fuel flowing.
 

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at the track
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try changing your fuel filter and cleaning your carbs too, because the fuel pumps on those bikes are weak
 

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Are we not men?
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To the best of my knowlege, the F3 does not have a fuel pump. It has a vacuum operated petcock and gravity flow.

As for the starter, don't worry about it. When my F2 would load up due to my ineptitude with the choke lever, the easiest way to start it was to dump the gas from the float bowls, and then crank it till it fired. The cranking allowed the cylendars to clear. I'd guess I cranked it for nearly a minute once. The starter was warm, but all was fine.
 

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Bring It!
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I don't know what the big deal is here. Normally when you start the bike you should just be able to choke it all the way and crank the starter PERIOD! That should be it. If it hasn't been started for a while or it's cold or something like than it might take some cranking but choking it is all you should have to do. If it doesn't fire up fairly quick you should get it tuned up or checked out.
 

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I didn't think there was a fuel pump on a carburated bike. mmmmmm. I thought the fuel was sucked out of the tank thru engine vaccum. Am I wrong?
I didn't think there was a fuel pump on a carburated bike. mmmmmm. I thought the fuel was sucked out of the tank thru engine vaccum. Am I wrong?
yep you are wrong, my zx9r is carb, and it has a fuel pump, and it does not run until the starter button is pressed, and the fooker has to crank for ages to start, if the float bowl is empty
 
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