Gas Tank Modification?? Can you help?

[V-Four]

For $1000 I'll make extra gas stops and deal with the craziness of trying to get back in my spot...

Youll be on a vmax..I dont think youll have any trouble getting back to your spot

 

[Miles Long]

Mate

My plan is to use 2 hoses. One for filling and the other one to let the air come out, this way you can use thinner hoses (1"?), That second hose will work as vent as well with a T splitter on top with a one way (inwards for venting) air checkvalve and the other tip connected to the aux tank (for refilling - circulate the air when fuel is draining from aux tank to main tank through the refilling connector hose). I hope you can picture all this... This will be my setup, and im almost sure will work fine. Just need to do some tweaking on the stock tank to close the filler, expand it and setup the 2 connectors for the hoses...

I think I know where you are coming from, but a sketch would be handy. As for venting, I use the original vent fitting on the top of the underseat tank, but removed the hose and tip-over valve(at the battery box location) I've rerouted the hose to a point higher than either of my gas tanks, and re-installed the valve. Just below the filler cap location of the auxilary tanks, I installed a 1/8" m.i.p. x 1/8" hose barb fitting. A short section of hose connects this fitting to a tee fitting spliced into the vent line. This arrangement provides venting for both tanks. However, you could probably just cap off the original tank fitting, and vent using a fitting at the filler pipe of the aux tank. My reasoning with using two vents was to expell enough air during filling, so as to not slow up the filling process. I wasn't concerned about letting in more air during operation, obviously only a tiny orifice is required. If you take off the hose at the tank fitting, you will see a brass fitting with a wee opening in the centre. My guess is that this was installed to restrict the flow of gas in the event of a tip-over, even though there is further protection downstream - the tip-over valve itself.
As for connecting to the existing tank filler pipe, I used a 11/2" PVC fitting. The O.D. of this size is almost exact to the size of the filler pipe. I used a rubber union connector, designed for plumbing applications, to join and seal the connection. Two hose clamps complete the seal. Even if there is a leak, the gas would be routed to the existing drain line in the rubber filler pipe boot.
In your case, if I read correctly, You would need a PVC tee fitting, 11/2" centre x 1" on the legs. But my concern would be using this small a size for the filler, it may restrict flow. This could be determined by fabbing up a piece of the 1" hose to the approximate bends required, taking your bike to a gas station, sticking the hose in the filler pipe, and trying it out. You will no doubt get some weird stares, but Michaelangelo, DaVinci, Ben Franklin, and Issac Newton all had to put up with this shit as well. All part of being a "pioneer". Nothing ventured, nothing gained!
Good luck

 

[Vmax Marine]

I believe that this is what you are looking for http://planetvmax.com/85-07vmax/carburetion/ufo-vgas-carburetion/vgas-ingenuity

 

[wildweasel_pt]

I think I know where you are coming from, but a sketch would be handy. As for venting, I use the original vent fitting on the top of the underseat tank, but removed the hose and tip-over valve(at the battery box location) I've rerouted the hose to a point higher than either of my gas tanks, and re-installed the valve. Just below the filler cap location of the auxilary tanks, I installed a 1/8" m.i.p. x 1/8" hose barb fitting. A short section of hose connects this fitting to a tee fitting spliced into the vent line. This arrangement provides venting for both tanks. However, you could probably just cap off the original tank fitting, and vent using a fitting at the filler pipe of the aux tank. My reasoning with using two vents was to expell enough air during filling, so as to not slow up the filling process. I wasn't concerned about letting in more air during operation, obviously only a tiny orifice is required. If you take off the hose at the tank fitting, you will see a brass fitting with a wee opening in the centre. My guess is that this was installed to restrict the flow of gas in the event of a tip-over, even though there is further protection downstream - the tip-over valve itself.
As for connecting to the existing tank filler pipe, I used a 11/2" PVC fitting. The O.D. of this size is almost exact to the size of the filler pipe. I used a rubber union connector, designed for plumbing applications, to join and seal the connection. Two hose clamps complete the seal. Even if there is a leak, the gas would be routed to the existing drain line in the rubber filler pipe boot.
In your case, if I read correctly, You would need a PVC tee fitting, 11/2" centre x 1" on the legs. But my concern would be using this small a size for the filler, it may restrict flow. This could be determined by fabbing up a piece of the 1" hose to the approximate bends required, taking your bike to a gas station, sticking the hose in the filler pipe, and trying it out. You will no doubt get some weird stares, but Michaelangelo, DaVinci, Ben Franklin, and Issac Newton all had to put up with this shit as well. All part of being a "pioneer". Nothing ventured, nothing gained!
Good luck

Thanks mate. It will take some time to get that thing done, but it will be done. I have other priorities right now and time is scarce...

I believe that this is what you are looking for http://planetvmax.com/85-07vmax/carburetion/ufo-vgas-carburetion/vgas-ingenuity

Yes something similar