19 20 Yamaha YZ450FX YZ 450FX 102mm 500cc Big Bore Athena Big Bore Cylinder Kit XR400 the incredibly stressed and torturous

the incredibly stressed and torturous environment in today's ultra high revving 4-stroke singles

while a Maxlock head stud kit enhances reliability

Compatible with all Polaris 900cc and 1000cc side x side models and years

Billet 22cc pump gas domes

All kits come with pistons

19 20 Yamaha YZ450FX YZ 450FX 102mm 500cc Big Bore Athena Big Bore Cylinder Kit XR400 the incredibly stressed and torturousP400485100068,BR9 11311 00 00,BR9 116A0 00 00,CW20012,40199M09700,S4F102000040,P400485160068,S41316216 18 20 Yamaha YZ450F YZ 450FX 102mm 496cc 500cc Athena Big Bore Top Cylinder Piston Kit Athena Part # P400485100068, S4F102000040, P400485160068, S41316216 Technical features Bore Diameter (mm) 102. 00 Bore Gain (mm) + 5 Compression Ratio 12. 3: 1 Displacement (cc) 497. 00 Vehicle compatibility YAMAHA YZ F 450 cc 2018 2019 YAMAHA YZ FX 450 cc 2019