YZ125XKEY FEATURES ENGINE The YZ125's liquid cooled 125cc two stroke engine provides thrilling mid to high rpm power, along with supreme usability. A revised compression ratio, revised YPVS timing and model specific CDI unit create broad, usable power suited to cross country. Intake design allows for a straighter, more efficient draw of air into the intake tract. High precision Hitachi Astemo Keihin PWK38S carburetor provides clean, crisp throttle response