54x54 Yamaha TZ125 Performance Kits
MCE Racing is now offering Kevin Murray's famous and championship winning "square bore" TZ125 for sale as a complete roadracing package. The MCE TZ-54x54 is a complete and conversion of the Yamaha to 54mm bore and 54mm stroke engine dimensions. It includes a custom MCE designed cylinder, head, and expansion chamber. It uses an HRC RS125 piston and flat ring (for reduced friction) available from a multitude of sources.

The widely accepted ratio of a 54mm bore by 54mm stroke helps transform the underpowered Yamaha into a more than just competitive machine. The advantage , however, does not end there. The cylinder is sand cast for superior reproduction of the original unit, and it is based on years of experience with both HRC and Aprilia designed grand prix cylinders. The design of the stock Yamaha TZ125 intake is in many ways superior to the RS125, and this, when combined with the MCE TZ-54x54 kit, yields a strong, torquey, easy to ride 125.
TZ-54x54 Kit Features:
  • Sand cast cylinder
  • Custom expansion chamber
  • Optimized combustion chamber
  • Uses inexpensive and easy to obtain HRC pistons
  • No increase in required maintenance over stock
Additional Information:
  • 2003 WSMC Championship Winner
  • KLS Quickshifter included
  • Carbon fiber parts (bracketry, clip-ons...)
  • MCE custom designed tailsection
  • Impeccably well maintained and clean
Pricing:
Complete bike: $4,000 USD
Contact Kevin Murray for more information.