extended fuel tank question


Feb 23, 2006
Lincolnton GA
2005 RIII
Ok here is my crazy idea of the day.
I'm running triple filters so I have the large space where the air filter used to be, I also have no cat box so there is that large space and mounting bolts available as well.
so, who is smart enough to tell me how I could rig a extra fuel tank upunder there to extend my range... if it was a carbed bike it would be easy, but with FI I don't know... wish I had a tank that mounted like my old cat box.... ( hmm maybe a use for that after all....)
I've contemplated relocating the battery into a box where the cat box used to be and installign some sort of tank under the seat, shoot just an extra1- 2 gallons would be nice
let me know what you think....
Put the fuel pump in the new tank and connect them together.I was gona try that to lower the center of gravity and not fill the top tank as much.John McKee had it figured out to.Go find a plastic tank out of a VRod that would fill that area and make the orignal tank false for storage.When you get it done we want pictures and how tos..Jack Try Moon eguip, they have a larger selection..
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wonder if somebody could take a stock cat box, and useing those measurements, create me a safe fuel tank that would mount down there. not sure if the stock fuelpump would suck fuel up from it, or if you would need to just remove stock one, and install a line from stock tank down, and then install your fuel pump into the bottom tank, In theory the stock tank would drain into the lower tank as the fuel from lower tank was consumed, bet you could get a 2 gallon square fuel cell down there. would be able to seal it better with the stock tank drainign into it.

if done correctly would add some range between stops and would be completely transparent. ( painted black to match)

There is a belly tank available for the Valk and I've seen a few. He was installing them at a Valk rally in Colorado. Shouldn't be too hard to engineer one since we already have a fuel pump, unlike the Valk.


The tanks are sturdy and the welds are top notch on these tanks.

Just another set of ideas.

I never talk about it here but I have an auxillary tank on the Bonnie. There is a 3 gallon NHRA approved fuel cell in the back of the sidecar that plumbs right into the fuel line to the carbs. It has an Earls quick disconnect so if I want to remove the sidecar, I just unplug the harness and unsnap the fuel line.

I use a solid state fuel pump just like the one in the picture of the Valk tanks. When I go on reserve on the main tank, I just switch on the tank in the tub and keep on riding. (When I ride it).:D

I got my fuel cell from Summit Racing.
I'm just knocking around ideas here...

The Rocket is of course fuel injected and it has a sealed unvented fuel tank with an electric fuel pump contained in tank. The fuel is under pressure as it is delivered to the injectors.

You could do one of two things possibly to add another tank. First would be to put a simple electric fuel pump in the remote tank and when you run low on fuel you would have to stop, pop open your gas cap, and manually run a hose (from your remote tank) and fill your primary tank from it, and then close the gas cap and put away the stuff from the remote tank. I don't like this idea but if you had to cover long distances between gas stations it would be better than nothing. It would be just as easy to carry a gas can.

You could buy a second Rocket fuel pump (with the fuel pressure regulator built into it) and install it into the remote tank. Here's where it gets a little tricky. Some pickup trucks had dual tanks (that were fuel injected... notably Fords) and they had a switch on the dash to switch between the two tanks. This switch turned on and off fuel pumps depending on which tank you wanted to use. I believe that the fuel pumps themselves used the fuel pressure regulators as check valves. If you didn't have some sort of check valve the fuel being pumped would attempt to refill the empty tank and drop fuel pressure. You need to turn off the fuel pump not being used because the fuel itself cools the pump and keeps it from burning out. A setup like this would allow you to switch tanks on the move. You would want fuel gauges for both tanks I would think. The remote tank should be made of something that is hard to rupture in an accident, and won't spark or conduct electricity. If done incorrectly it could be a fire waiting to happen.

I like to stop every couple of hours or so anyway :D so this setup probably isn't for me, my rides are controlled by Monkey butt to a large degree.