This Lifan kit coverts your motor into a 140cc motor.  This kit wont fit 125cc vertical motors.  The kit comes with everything shown in the picture below. It uses a 54mm wide, 42mm high piston, uses 15mm wrist pin..  Check your piston, if your have a 13mm wrist pin. then this kit wont fit your 125cc motor. This kit wont fit all 125cc motor, only ones that use 15mm wrist pin.
If you do not make sure ,it fits your bike.Please email us.