Hello. My second oil change (at 139 miles) had more metal. I did a third at 223 miles. It is normal.
Did you do any other maintenance at 600 miles? The book recommends checking for a few things at that point. I'm nearing 600 myself, and going to check valves, brakes, bearings, chain, air box (sandy here), lines and hoses in addition to another oil change. I also got Lucas marine grease for the swingarm pivot bushes. Wheels are important, too!