Does it have something to due with how 7075 aluminum bonds? All YYR yoyos are solid and I know that they are all made of 7075 aluminum as well as Yoyo Joker.
More recently Onedrop has released their code2 anodized solid blue. soooooooo yeah
-Ben
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2011 supernova wasn’t all solid colors. But I think its because 7075 aluminum is harder to anodize but YYF went the extra mile by accepting the challenge and destroying it.
YoYoFactory and Turning Point have both released a number of multi colored finish 7075 yoyos.
Isn’t the code 2 made of 7075?
I think you’re over generalizing here.
Only the new GZR release.
Spottedbanana ha done some beautiful work on 7075 aluminum 
and yes it’s because of the difficulty in anodizing it