<page_title> List of Grand Prix motorcycle racing World Champions by year </page_title> <section_title> List </section_title> <table> <cell> 1990 <col_header> Year </col_header> </cell> <cell> United States John Kocinski (Yamaha) <col_header> 250cc </col_header> <row_header> 1990 </row_header> </cell> </table>
John Kocinski is a Grand Prix motorcycle racer, who won the 1990's 250cc World Championship title.