Hi, was wondering if anybody could offer an answer to my query! I own an 04 wr450f and recently went to check the valve clearances to find, when i removed the straight plug (the larger one at the bottom) to align the piston to top dead centre that engine oil was coming out. The space behind the plug was not full of oil, it only started to come out when the plug was removed. Is this normal, or is there an oil seal or something behind the casing that has gone?? Any advice would be greatly appreciated!! cheers.