PVC Tank How To

1. Figure tank size. I built my tank to go under my top tube, so I measured the available space from my head tube to my seat tube and the clearance from the top of my engine to my top tube. If you want to go behind the seat measure appropriately, or if you have a rear rack that you want to mount it on measure away. How much your tank will hold use the formula: Volume= 3.14 X Radius Squared X Length of Pipe. This will give you volume in cubic inches, google cubic inches to gallons for a quick conversion tool. Given my parameters I Built my tank out of 3 inch PVC and made it about 14" long.
Volume = 3.14 x 1.5 squared x 14 or 98.91 cubic inches or .42 gallons

2. Cut PVC. I cut a piece of 3 inch PVC about 11 inches allowing about an inch and a half of length for each end cap. put end caps on to make sure it fits in the desired location adjust length as necessary, but don't glue yet.

3. Add fittings. I used a step bit to drill a hole in one end cap. The step bit allowed me to make the hole slightly smaller than my fitting, and with a little bit of muscle I was able to thread the fitting into the pipe. I used scd 40 PVC it was plenty thick, Scd 80 would be overkill. I did the same for my fill pipe fitting on the tube.

4. Glue it. Use Seal All or some other fuel proof adhesive/bonding agent/ glue. Unthread your fittings apply glue and re install. Glue end caps on.

5.Vent Cab I used a standard brass garden hose cap, drilled a hole in the center then inserted a slotted peice of plastic (sHeet metal would work as well) see pictures below.

Materials list for fittings will be in following post. I plan on using a universal shut off kit found at Lowes instead of a petcock to shut off fuel, it will be in materials list.

Materials:

Fill pipe 3/4 MHT x 3/4 MHT or 1/2 FHP Hose Adapter. I wanted the finer thread on one side to thread into pvc.

Outlet1/4 x 1/4 brass adapter. As long as the barb side is 1/4" the thread can be what ever you want, I found the smallest thread possible.

Cap 3/4 Inch Garden Hose Cap. Generic cap you will need an extra garden hose gasket to act as a retainer for the plastic/sheet metal vent piece.

PVC Diameter will be determined by desire application and/or required volume just make sure you buy 2 pvc Caps of the same size, I found that anything over 4" diameter gets crazy expensive.

I will hopefully have the tank cleaned and mounted for pics before the week is out.

Almost forgot here is the fuel cut off alternative to the pet cock:
Precisefit Gas Shut Off Valve

yes the extra piece is to keep fuel from sloshing out as long as none of the slots in the plastic line up with the center hole. You can also buy a hose cap with a 1/4 inch barb attached to it and just add a line and/or filter for a vent, I just wanted something that looked a little sleeker.

I also would have threaded the pipe but I could not find the tap and die set so I cheated.

Here is the tank mounted and ready to go.

yes I did the intake for noise (plus the soda bottle just adds to the look) It did not reduce sound an awful lot, but it did change the pitch and gave it deeper sound, I still have to add some sort of filter element/packing into the bottle portion of the intake and I believe that will make a noticable difference with the intake noise.

I do have a funnel but it came with the fuel can, it is 3/4 inch so it is a bit for a normal fill pipe, but most small engine fuel cans would fit it.

The red piece I fabricated out of a piece of plastic I found in the shed, sheet metal would work, you just want to slot the side enough to let the air by but stay seated between the rubber gaskets. Keep the slots out of the center of the insert so that gas won't slosh through the hole in the cap

I have not found any leakage at all in the cap.

My dad is a retired plumber so I had a garage full of pvc to play with so One of my original thoughts when I stared seriously considering pvc was to use like a 3 inch T with like an 1 1/2 take off and just cap the ends of the T and use the take off as the filler. I went with the brass fitting because I liked the lower profile and it "fits" the bike better.

My dad is a retired plumber so I had a garage full of pvc to play with.

If I had harness leather and I knew what I was doing with it, I would definitely finish it like one of yours SB but all I had one hand was Smurf blue rustoleum paint...