Kawasaki KX125 2003-2007 Athena 144cc 58mm Big Bore Cylinder Phathead yz65 8cc 72mm 93 octane -

8cc 72mm 93 octane - Revised squish clearance

With a one way valve built in to the breather vent designed to block the outflow of fuel when the tank is upside down(crash scenario)

6cc 100+T04 5

9cc 100+ octane

SX51 (100+ octane)

Kawasaki KX125 2003-2007 Athena 144cc 58mm Big Bore Cylinder Phathead yz65 8cc 72mm 93 octane -We replicated the Athena chamber to offer the best performance for your two stroke big bore kit. Athena KX125 144cc big bore compatible. Use the Athena Big Bore Gasket. Phathead Kits include a head shell with one combustion chamber, cylinder head nuts, copper washers, some stickers for your bike and tool box and installation instructions.. Phathead cylinder heads are made of 6061 T6 billet aluminum. The material is stronger and transfers heat better