My 500 was sitting in my garage for months..with a fouled plug, i put a new plug in today just one i found, b7es cause i didnt know it was fouled so i put her in not thinking about the gas..started her up took it down the road it takes off, but in high rpms just doesnt move, has to be the gas right? i drained it out and its clear as water..and i use RED oil..should new gas and oil fix the prob?