Mmm if you didn't put any after run before you store it, it's probably rust inside. a one year set aside need some preparation to avoid corrosion. the first thing you got to do, is to tear down the engine, checking all of the component: bearing, crankshaft, piston, sleeve everything. if you don't know how to get that done, 2 possibility: you got to your local hobby shop ( what we call here LHS) and get some mano-to-mano help, or re-post your problem on the MT2 tread. and get some pic of your engine to help the MT2 guys out about parts that your not sure of the name.

don't worry, if you need help, your at the right place. but i hardly suggest that you repost all this in the MT2 tread.