Re: Custom Aluminum Cylinder Tank Build Input
i had the same idea a few years back. the reasons i abandoned it where; a tank tha small hold roughly 24oz of fuel, about 1/5 of a gallon.
that would give you about 20-30 miles on a china 2-stroke. i used to ride 30+ miles daily to work and back and needed more gas.
there are many different double bar frames made over the years with different spacing between the bars. on a wide spaced frame like a worksman, the tank would look small and goofy. on some older bike's there's 2.5" spacing, plus many different tapers, from angles to sweeping bends. fitting these frames would be tough for a universal tank.
cost is another factor. getting a welded cylinder is cheap but adding in a quality petcock, bung and cap brings your cost up. too make it up a tank would end up retailing for 150 to 200 bucks.
not to offend anyone, but the majority of bike owners are, uh, lets say "thrifty," and think that since they're motor costs under $200, tanks and expansion chambers should be a lot less than that, even though the same amount of work as building custom motorcycle parts go into it.
the double bar frame isn't as popular as a box store cruiser, so your customer base is limited. also, many builders of vintage bikes have the skill to make their own tank.
if you're serious about making tanks, a universal behind the seat tank may be more profitable.