WISECO PART NUMBER: PK1019. WISECO HIGH PERFORMANCE TOP END KIT WITH FORGED OVER BORE PISTON AND COMPLETE TOP END GASKET SET FOR YAMAHA YFM350 APPLICATIONS. 1999 Yamaha YFM350 Moto 4. 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 Yamaha YFM350 WT Big Bear.