im new to dirt bikes and 2 stroke engine and pick up a 1991 kx 250 2 stroke as a project to go out and ride with a few friends. when i bought it i was under the impression it was a 94 and turns out its a 91, seems that internal engine parts are harder to find for this year. the engine has a seixed crankshaft and bent rod my question is am i able to put a newer engine say 92-01? with few modifications or the newer bottom end with my 91 top end ive rebuilt and built plenty of race cars and engines and generally know my way, but dirt bike are a whole new ballpark for me! thanks for any help!