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The gas tank has 4 places to stick gas lines on 2 front left and 2 back right I'm talking about outside tank I'm stumped plus ware does fuel pump gets it power. I see no place wires on the inside of the tank or going through it.
 

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The gas tank has 4 places to stick gas lines on 2 front left and 2 back right I'm talking about outside tank I'm stumped plus ware does fuel pump gets it power. I see no place wires on the inside of the tank or going through it.
It would help if you include a few details like:
Make, model, year of motorcycle
Fuel injection or carburetion
Any mod's or customized parts

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The front left are your FI hookups, feed and return. I don't recall what the others are - possibly drain holes for the filler cap?
 

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Drain and Vent
There is NO vent on a pressurized gas tank on drain if your bike is EFI, electronic fuel injection which most are and have been for some time except a few Harley has built that have carbs, I personally love carbs even if they are really bad for the ozone, really horrible honestly. Mr. cmonSTART is quite correct as I just changed out my tank, 09 1200rt and broke one of the plastic quick disconnects but have brass one's coming, pain in the damn ass, BMW is damn cheap with plastic, it's good for some things but not for all.
 

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There is NO vent on a pressurized gas tank on drain if your bike is EFI, electronic fuel injection which most are and have been for some time except a few Harley has built that have carbs, I personally love carbs even if they are really bad for the ozone, really horrible honestly. Mr. cmonSTART is quite correct as I just changed out my tank, 09 1200rt and broke one of the plastic quick disconnects but have brass one's coming, pain in the damn ass, BMW is damn cheap with plastic, it's good for some things but not for all.
Not correct. I don't know about later Beemers, but my '03 R1150RT does have a vent in the fuel tank. I'm pretty sure all the fuel injected oilheads do. There are four hoses coming out of the tank: high pressure fuel out, high pressure fuel return, low pressure filler cap drain, and low pressure tank vent. The tank vent line runs back to the carbon canister.

And you're right about those plastic quick disconnects. I broke one and dumped a bunch of gas on my garage floor. NOT a good thing. I now have the brass ones.
 

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Not correct. I don't know about later Beemers, but my '03 R1150RT does have a vent in the fuel tank. I'm pretty sure all the fuel injected oilheads do. There are four hoses coming out of the tank: high pressure fuel out, high pressure fuel return, low pressure filler cap drain, and low pressure tank vent. The tank vent line runs back to the carbon canister.

And you're right about those plastic quick disconnects. I broke one and dumped a bunch of gas on my garage floor. NOT a good thing. I now have the brass ones.
If yours has a vent the tank is not pressurized, it is not possible to have a vent in a pressurized tank or the tank is not pressurized, I am finding this out with my tank. I thought I had a vent also but No, the opening in the top of the fuel pump is a drain hose for when I or anyone else over fills their tank, I knew there had to be one but mine was closed with a lot of dirt in it so i drilled it out, the two and a half inch long steel vent have a hose connected in the fuel tank and now I'm trying to figure out where the hose on top is suppose to go, to the middle where most of the wiring is or just off to the left side since there was no hose connected at all. The first owner did not know how to work on bikes and I do on most others but I'm really learning on BMW's, they are very different. IF you are calling the fuel drain a low pressure I will call it a NO pressure as there is zero pressure on the hose, low pressure means there is some, I did study this stuff in college, there is not enough pressure in side the gas tank even pressured up for the heavy rubber hose to be in closed in pressure as the pressure does not become great enough, some one who knows more about BMW's than I do suggested this. I would like to find out what amount of pressure is in the tank when you turn the key on, I don't know exactly what type of pressure is needed for the fuel injectors to work correctly and I don't know how all of that works completely although I do know how it is supposed to function or the theory and hope it all functions as such.
 

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There is always pressure otherwise you would be in a vacuum. So there is pressure on that hose even if it is only atmospheric.
 

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Right, my fuel tank is not pressurized, but the bike does have EFI. I'll have to admit I've never worked on an R1200. A pressurized fuel tank sounds kinda dangerous. And I have to believe there's a way for air to get into the tank to replace the fuel that leaves.
 

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There is always pressure otherwise you would be in a vacuum. So there is pressure on that hose even if it is only atmospheric.
Yes, I am quite aware of this and I believe you are quite correct, I do know plenty about atmospheric pressure and other such stuff to do with the upper atmosphere as I have a ph.d in astrophysics and I don't at all look at the out side world as having pressure even though it does have such a high amount, 14.6ibs or there about which really sucks some times and is great others, gravity is so much fun. I try real hard not to get to technical with physics stuff as most have no idea about it and their eyes glass over and they start yawning, such fun.
 
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