Balanced crankshaft marked "85CC". -POWERFULLY DESIGNED 52mm BORE HOLE PISTON FOR ULTIMATE PERFORMANCE! STANDARD ENGINES ONLY HAVE 47mm! BENEFITS OF THE RUNFAST TM SUPER ADVANCED COMPLETE DIY HIGH PERFORMANCE SIGMA 2-STROKE BEYOND STANDARD 66cc/80cc MOTORIZED BIKE ENGINE ONLY HIGH PERFORMANCE SUPER ADVANCED SYSTEM.
