Hey everybody, I have 98 yz400f with head problems. I took the top end apart and found the one of the buckets had wore a grove in the head. I was going to buy a used head for it, I also heard that I should replace Not exactly sure if it's the wrist pin or rod because they would break if you would bore the cry lender out. So here is the question can I put a 426 cyclinder and head on the 400 bottom end or would I be better off just buying another. 400 head?? Thanks for your help!!!