If it is the same as a ZZR600, and I assume it will be, then the bulb is held in by a metal hook which is clipped under part of the housing and hinged at the other end so it doesn't fall off. Once you remove the clip by pushing it in at the same time as slightly sideways the bulb will be able to be pulled out of the light assembly.
Pull the rubber boot off first, and the plastic connector on the end of the bulb and you should be able to see it. You don't need to pull out the instrument cluster, although for the 600 you need to have triple-jointed elbows and it was easier to remove the mount for the brake line.
The bulb only fits in the housing one way, as per the tabs on the metal bulb mount. If you don't have it in correctly it won't allow you to clip it back in.
Here is a crappy-looking photo scanned out of the ZZR600 manual, the hook you're looking for is the part highlighted as
A:
![Image](http://mmasterman.bigblog.com.au/data/9/47055/image/backofheadlight259994277292809214120091214115456.jpg)
The end that unclips is the end with the triangular loop diagonally opposite the end of the arrow.
This may help too:
http://www.ksrc-au.com/html/zzr_headlight_change.htmlReplace the bulb as per above with a 55/100W unit, the stock bulbs are shite.
HTH, Mick
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