Re: Painting a yellow to black fade...
If you want to do that fade I recomend this dont use rattle can paint unless its your only option, your best bet would be to find a local body shop an see if they would be interested in helping you out for a price obviuosly.if you must do it your self , look around on line I have found refillable spray bottles an compressed air in cans that screw onto the refill bottle. spray whole bike yellow first , then determine how big of a fade you want , on average here in the shop we tend to make the fades as wide as possible or about 30% of the size of the area which has total coverage in black for your example.
Technique : achieve your coverage in black lets say your coverage with this color is in an area 12 inches long then thin your paint to a ratio of 1.5 to 2 parts thinner an make the fade with this mix at your over spray edge apply your first coat of thinned color over an area about 1 1/2 inces wide using a 50% overlap allow to flash off then 2nd coat using same technique an build up to desired distance. I do reccomend practicing on a peice of old sheetmetal till you are comfortable , because doing this on tubes is difficult.
hope you get a good result.