125-200cc wr 250 common engines

Hi, I just bought a wr 250 that runs bit has no power. I'm about to investigate and first thoughts are the rings/piston/head as there is oil blowing out the exhaust port. My problem is I can't find a workshop manual for it. I think it's either a 1996 or 1998. I have found a manual for a 2002 model but am unsure if the engines were still the same? I need tolerances for piston and head so I know if the bore is worn and what to have it reported to. Any help on any of this would be useful thanks

The best thing to do post up a picture, from memory i think the 98 engines where different from the 99 - 12 engines. There is some where on the forum a thread with a link to all the manuals use the search to find it. Unless someone comes along who can remeber the link.

Also remove the power valve covers and check the little plastic rod hasnt broken. it may also be worth checking that power valve is clean and free to move.