High Compression/High Altitude - GY6 172cc (61mm) Scooter Performance Kit and Kaboodle

  This is our High Compression/High Altitude kit. This kit will come with a domed style piston. This raises the compression ratio. This is a must if you ride in an area that is 3000 feet or more above sea level. The higher you go in elevation, the more your compression is lowered. You can install this kit in a sea level engine no problem. Just know you will need a high torque starter and performance starter clutch. The high altitude people won’t need those parts. This has all the performance you need put into one kit! We have spent years testing and selling other kits. Some things we liked and others we didn't. We pieced this kit together with the best of the best materials (rings, gaskets, springs, and metals). This high compression 171cc kit (or as some call it 172cc) requires no case boring unlike some others on the market, and is also a "drop in" kit. It is the largest big bore kit you can do on the GY6 A motor (Chinese GY6 QMJ157). Like they say, “there is no replacement for disp