If you're having spark issues with your YFM 400 then it's no brainer to get an upgraded coil on the bike to improve your spark
Kawasaki (K) Z 1100 R1 (1984-1984)
This set of steering stem bearings will replace the original factory head stock bearings on a YZ250 for the years shown above
This set of headstock bearings are taper roller style and have been manufactured to replace the original steering / headstock bearings on a Kawasaki Z1000 / KZ1000 for the years shown above
Suzuki LT 250 R (RF-RM) (1985-1991)
Cylinder Barrel Kit: Yamaha YZ85 YZ 85 (2002-2018) Yamaha XJ550 If you're having spark issuesBrand new cylinder barrel kit to fit: Yamaha YZ 85 (2002 2018). This is a high quality ceramic, lightweight top end rebuild kit to fit a Yamaha YZ85 for the years and models shown above. You may find cheaper aluminium cylinder kits for your YZ 85cc online, but you can't beat the quality that a light weight ceramic cylinder and piston gives you. The kit includes the following: Cylinder Barrel Jug, Piston, Piston Ring, Gaskets, Gudgeon Pin, Circlips and