I bought an XR600R that was abused pretty bad by a previous owner and decided to take it on as a project hoping for the best and of course going way over budget. I completely disassembled the bike and sent the motor to AMI in Puyallup for cylinder resleeve and a rod kit. They told me the head was about to go and I decided to risk it and put it together and hope to not have to spend any more money for at least 2 or 3 rides. Wrong. The bike is dumping oil in to the chamber after startup and I'm sure I should just replace the un-rebuildable (according to AMI) head. Now, I found some parts on eBay and Craigslist, etc., but get mixed information over head compatibility. Some say '88 to late 90's fits my bike, but when I see closeup pictures of older heads they don't look different (like '86). Of course some bikes have black motors, while mine is unpainted aluminum, but other than that what's the difference? I want to ride when September finally delivers the weather we've been expecting all summer.