Posting here (as well as the 250 forum) as I am a ex-426er and know the brains on this forum.. Also, would be the same situation on a 426 as my 250F... *************** I may have really screwed myself somehow.. Doing the 03 cam mod on my 02 YZ 250F. Included pulling the flywheel and replacing the timing chain.. Tonight I had the chain on the new cam and was trying to turn the motor over to test my timing and noticed a grinding noise (at the crank) when I turned it over and it felt really rough and tight at sections, then would cycle through easily. At first I thought it was the force of the valve springs on the cams, but I realized that it sounded and felt worse than that. Took the chain off the cams and it still did it. Seemed to get worse, but could be my imagination/panic.. There is no spark plug. I pulled the flywheel and the chain off again to see if there is anything obvious and there is some strange metal shavings in the case.. Sounds really bad and now I am not sure what to check next.. Again, have the plug out, no timing chain, no flywheel or stator plate and I can *not* move the kickstarter - and am afraid to really put pressure on it. Thinking the crank should easily spin over. Is this correct? I was tired the first night and turned the motor over clockwise trying to find my timing mark. Manual says that can cause "damage" - but doesn't say what kind of damage... Anyone have any ideas?? I am stumped and really nervous that I've got a major problem on my hands. Thanks in advance.