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 Stage 2: single-cam motor. Excellent top-end power with great over rev. Uses stock auto-decompression mechanism. Uses stock valve springs.

 Stage 1: Dual cam engine. Intake and exhaust cams sold separately. Good midrange and top-end increase. Cam uses stock auto-decompression mechanism. Uses stock valve springs.

 Stage 1: Dual cam engine. Intake and exhaust cams sold separately. Good midrange and top-end increase. Cam uses stock auto-decompression mechanism. Uses stock valve springs.

OE Part Number(s):YAMAHA: 2S2-11400-00-00YAMAHA: 2S2-11400-01-00For Models:2006 - 2009 Yamaha YZ 450F

The first and only asymmetrical piston for 250cc and 450cc applications!100% fully machined billet pistonDyno proven power gainsExclusive custom lapped top ring and matching precision machined ring groove provide improved ring seal and break-inArmorGlide...

Stage 1: single-cam motor. Stage 1 has improved power at all RPMs over OEM. Performs well with stock air box lid and exhaust. Uses stock valve springs and rockers. Uses stock auto-decompression mechanism.

Stage 1 ITR: Dual cam engineIntake and exhaust cams sold separatelyExcellent low end to midrange gainsUses stock valve springs

Stage 1 ITR: Dual cam engineIntake and exhaust cams sold separatelyExcellent low end to midrange gainsUses stock valve springs

OEM-style statorsDirect plug-in stators complete with all rubbers and OEM-style plug end (unless noted)

OEM-style statorsDirect plug-in stators complete with all rubbers and OEM-style plug end (unless noted)

Hot Rods Bottom End kits include everything needed to complete crankshaft installation:Hot Rods main bearings and seals kit (Main seals included when applicable)Complete engine gasket set includes all gaskets and seals for complete engine rebuild (Does...

Hot Rods Bottom End kits include everything needed to complete crankshaft installation:Hot Rods main bearings and seals kit (Main seals included when applicable)Complete engine gasket set includes all gaskets and seals for complete engine rebuild (Does...