Nope, sorry, our 3.4's are grey backed! ...hold on for this one, but we are looking into having chromed ends on our new secret Darkside motor- Limited time though! If this works out, it will feature chrome end and DKS logo on casing. Very Limited, we will do a contest and... this is the last time I will mention this motor before release!
anyway to answer question, no, color doesnt always go with speed. we chose grey because it goes with the name "Darkside" our monkey rotor is pink because our spokesmodel likes monkeys and her favorite color is pink... yes she's my girlfriend, that is my little dedication to her in way!