This place never ceases to amaze me...
white is the combination of all colors...
black is the absence of all color... and soul... its common knowledge...
We see "reflected" light, not the item itself.
When white light hits a white painted 5 gallon fuel tank, all of the colors (frequencies) bounce (reflect) from it and stimulate the cones in the retina of our eyes which, in turn, send an electrical stimulus to the brain. The brain then interprets that stimulus as the combination of all the colors of light that reflected from the tank; white.
Nothing reflects off a black tank and the resulting interpretation is nothing; black.
Now here is the kicker. The black tank absorbs all the frequencies, making it heavier. You may argue that light has no weight, but if you've ever read Stephen Hawkings, you realize that light is actually particles with a specific gravity. This weight adds to the weight of the bike. Now, white bikes relect all these nasty particles back into the ether; remaining light, lean, and mean.
This has been a public service.