BMW isn't the only car that requires optional California emissions packages to be registered in the golden state-virtually every manufacturer is subject to the restrictions-hence the term for a performance car or sports bike that its a "49 state" model-meaning no Cali emissions.

 

First off the reason you see green stickers on banshees,yz400/yz426/wr400,drz400 when they are supposed to be red is because someone knew someone at dealership and got them to check green sticker box instead of red on dmv form.Illegal,yes and no.Could easily be called a simple mistake but we all know better.The raptor will probably be green sticker legal standard just like the bomber due to mild cam and compression specs ie.less emissions,compared to 2-strokes and yz400-426 and drz400's.
Second,any vehicle not originally sold in calif has to pass smog test as well as visual component test(regardless if it passes sniffer test),plus pay extra smog impact fees to register in state.And BMW's especially 3-series sell like mad here in sunny calif.