I´ve had my xj550 for 23 years. I´ve only got 12000 miles on it. It takes a while for it to warm up. sometimes I have to keep it chocked halfway for a mile or two before it smooths out and idles nicely at a red light. Last summer it started to leak oil from the #1 and 2 side of the head. Is there a gasket for that or is it form-a-gasket. Never had it apart and the head bolts seem tight.