My son started my 2009 Triumph Bonneville SE setting the choke to full. He walked away and forgot about it. An hour and a half later I found it sputtering in the garage. It was overheated and had leaked a little oil in certain spots. I let it cool for a couple of hours and now it runs terrible. The plugs were fouled so I changed those, still running bad. How bad is the damage to my bike? What should I look at doing next?