[rattlsnak]

US-market Yamaha YZs were yellow and black from 1975 through 1984.
Overseas and Canadian market YZs went to the white and red long before us, sometime in the 1970s. This explains why you see confusing images of early 80s models.

YZs were white and red worldwide from 1985 through 1990, with the exception of the 1989 and 1990 YZ250WR, which was white and blue. The 1990 factory race bikes had a very hideous white with dayglo orange seat cover look.

1991 and 1992 models were white and magenta (each year a slightly different shade).

1993 YZs were white ad purple...1994 they went to a purple frame as well. The 95s had a slightly different color purple. 95 factory race bikes were blue.

In 1996, they were dark blue/white. 1997s were navy blue. and so on.