+1 on keeping the paint original.
If you've got some dollars to throw at it, put a set of Gixxer 6-pot front calipers on it, then upgrade the suspension and pay to have it set up properly for your weight. I've got a WP nitrogen-charged rear shock on the back. I've had several mechanics want to "help me out" by offering to swap it for their original rear shock.
![Wink ;)](./images/smilies/icon_wink.gif)
Also, if you want to be able to throw it into a corner a bit quicker, flip the rear axle 180 degrees, putting the axle at the bottom of the tensioning cam, instead of the top. This lifts the back around 30mm, changing the rake. TOTALLY changed the handling of my bike. The only downside to this is it's now a LOOOOOONG way down to the stand!!!
Another good mod is an HID conversion. I've not done it yet, but have seen it done on another ZZR. They kick arse over the old headlight.
There's plent of poke in these big girls without needing to go for drastic changes. Toss away the stock air filter for a K&N. I'd keep the exhaust original, but only because I love the twin pipes. The 4-into-1 conversion isn't my cup of tea.
Congrats on buying the greatest Kawasaki ever built.
![Kuda :kuda:](./images/smilies/kuda.gif)
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