Piston kit Yamaha FS1 40,75 mm

The piston must be oiled during assembly and do not forget to check the needle bearing! For the longest possible durability and service life, the piston should be "run in" during the first approx. 20 miles. *Pistons marked with an arrow, the direction of the arrow should be towards the exhaust port. *Pistons marked with IN, IN should be towards the intake.