Hi. I´m about to buy a motorcycle for summer, and there´s one Kawasaki GPX 750 R -89, that really cought my eye. Looks ok to me, but I have heard that particular type has some trouble with intake valves (valve streching or something). Is this a problematic defect or is it something that can be avoided somehow. Can valve streching damage the engine, if not taken care of appropriately. Many thanks to all who responde.. :)