- High compression 54mm piston with rings, pin, & clips and head gasket kit (replaces your low compression dished or flat top piston)

With your cylinder bored to 54mm, this piston will fit the following 124cc engines: GPX, Extreme, UPC, Thumpstar (any 124cc engine with a 52.4 x 57mm stroke and 13mm piston pin).  Cylinders can be bored locally and is a fairly inexpensive job - typically $55 to $75.

This will make a huge difference in performance over your stock setup - Click here to see the difference between a 52.4mm "dished" stock piston (GPX/Extreme and others) and our new piston.

Note:  The gasket kit is a Honda type gasket kit and the head and base gasket will fit models like the Extreme, but will not fit perfectly on some other Chinese brands - will require modification to the head/base gasket or use of the stock gaskets.

For additional performance, add the 26mm carb kit and the MX CDI available in this section

See the Performance Info section for additional information on our performance parts.