Click the pics
Max´s bike is a Kawasaki ZZR-250. Look at the bodywork, the rear turning lights and the shape of the headlight.
What they did to Max´s bike for the show was to remove the ZZR and 250 logos on the bike and called it a "Ninja".
The ZZR series isn't referred to as Ninja only the 250cc models and since Max´s bike is supposed to be a 650cc, however -
There is no 650cc engine for the ZZR. The reason to they refer to it as an 650 in the series is simply just cos they want Max to be a bad-ass chick.
Truth is Jessica Alba couldn’t handle the power of a 600cc bike, said so herself.
Probably to heavy for her to, so they used a 250 and referred to it as a 650 in the show.
I also heard rumours that its custom built, that they changed the exhaust and the engine.
Wouldn't be suprised, as the orignal cans look naff and the exahust probably have given up, mine did (Kawasaki's run hot).
Other details which give away the true identity - rear light shape, smaller discs, small tank, pressed/boxed alluminium frame.
This type of frame is too weak for a 195Kg bike, note the difference between shiny bar and mono-cue frame (engine as stressed member).