The Kohler K341 engine is a good unit,and well worth rebuildig. It normally should pull 60-80 psi,and sometimes higher,depending on the age.A Kohler dealer could tell you exact psi. These engines are strong,reliable,and still quite popular. The price you gave for the kit isn't too bad,if it has the gaskets,ringset,and any o-rings. I'm not familiar,though with the type of 2-speed drive you mentioned. Can you post some pictures,perhaps? If the engine seems "tired",but doesn't smoke/leak oil,it may only need a good tune-up.Check the points for burning/gap (.014 is a good start),and chech the coil for a hot spark.Since it's a battery/coil ignition,like a car,weak voltage into the coil will cause poor running.