I rescued this 1983 GPz 550 from a software engineer. I got it for free, and dumped nearer 2 grand into it for parts, and my labor to bring it back. The idea going in was a trackday toy and sometimes racebike. I got bored with the wobbling thing and sold it. I had upgraded the fork internals along with a complete rebuild at that end including wheel and steering bearings, brake pads and steel overbraided lines.
The motor was stock save for a re-jet and freshened cam chain, tensioner, new clutch, sprockets and drive chain. Sealing the thing all back up and getitng the carbs sorted took the longest.
A friend had offered me a Basani headed for free, that was in good shape. I considered it, but went with the stock for the looks.
The rear shock was custom from Works Performance. Swinging arm bearings/bushings, helped but it still flexed a lot with modern rubber sticking it to the road.
The tank was dented on all sides, but held fuel. Smaller Ducati turn signals looked a whole lot better.