[19 December 2007]
About halfway through November I got around to finishing up the bits that were left and painting the entire bike. I sprayed the entire thing navy blue, and put white tires on it.
One problem I noticed on the first test-ride with the frame gas-can: the gas can stuck forward enough to interfere with pedaling. Another problem I noticed after painting was that I had spray-painted the gas can blue to match the rest of the bike, and the frame bracket scraped the paint off the gas can badly.
In the photo above, you can see where the frame bracket scraped the paint off. The problem with using these plastic gas cans is that I did not know that they change shape when you put fuel in them. When I built the frame bracket, I had the gas can empty, and when empty the flat sides curve in from the corners about 1/8-th-inch. I bent the frame bracket very nicely around the empty gas can, and it fit quite well but was still easy to lift in and out. I was even worried that I would hit a bump and it might fall out if it was empty.
The first time I tried test-riding with the attached gas can, I filled it up completely with fuel and tried to place it in the frame bracket.... and that's when I realized that when full of fuel, the sides of the gas can bulge out about 1/8th inch. It has to be forced in and out when full, and quite a bunch of paint got scraped off the first time, and more came off each of the next few times I put the gas can in or out. So the lower part of this gas can just isn't going to stay painted as it is.
I tried to line the inside of the bracket with some pieces of duct tape, but the gas can simply fit too tight when full, and the duct tape wouldn't stay put. I didn't put gasoline in the can to begin with because I was using a welding torch to hot-bend metal when I was making the bracket, and didn't want the added fire hazard. Water wouldn't be a problem though, and would be even heavier than gasoline, so you'd be sure to leave enough room for the full can.
(To paint the gas can and the engine's plastic shroud, I used some Rustoleum "plastic" paint, which seemed to work quite well. It only took a light coat to cover the base colors, and it dried to the touch within just a couple minutes, but obviously it isn't scratch-proof.)
I could cut the frame bracket in a couple spots in the horizontal loop and weld in some short extension bits, but that's still not going to solve the problem of pedaling interference. If the engine ever quits, I do want to be able to pedal the thing home. I decided to just look for some other kind of tank to use.
I thought of maybe using a damaged acetylene welding tank or an empty fire extinguisher tank (rather ironic I thought) but couldn't figure out any easy and economical way to get ahold of either of them.
I browsed the online surplus sites for some time and happened to run across what i thought might be something workable.
I found a hydraulic tank at Burden's surplus center that looked like it would mount fairly flat, so I ordered a couple.
http://www.surpluscenter.com/item.asp?UID=2007121915253737&item=9-7481&catname=hydraulic
I plan on mounting one of these roughly in the spot that the plastic can is now, but a bit further back to avoid pedal interference. The second one will be mounted on the same side but further back, underneath where the rear rack is.
A few notes on these tanks, for the interested: the metal these are made of is pretty thick, if you had to punch it hard enough to leave a dent, your knuckles would end up bleeding. The mounting plate welded on the back is one-eighth inch thick steel. The fill cap is a radiator-style with a cork seal, and it doesn't have threads--you turn it a quarter-turn and lift it to get it off. The cap has a hole in its center so it may be vented both ways, but it's not going to build up any positive pressure for sure because of the way the cap is held on. I plan on using it just like a regular gas can, putting fuel in and dumping fuel out through the top filler neck. The plugs that are in the two 3/4 NPT connections are just flimsy aluminum things for shipping, they only have about one turn of loose-fitting threads, so I'll have to find some real plugs for those holes. The tank is unmarked except for a sticker on top that says what ID number of employee tested it.
Once again it's cold outside. I don't know how much work I'll be doing during the cold weather.