Dirt Bike Engine

Athena - 09310975 - Cylinder Kit - 47.50 mm - YZ85FeaturesSpecially designed, high performance, hard anodized power valves (cannot use OEM)There is an aluminum cylinder head with a removable bronze dome allowing for a higher compression ratio and...

Athena - 09345863 - Top End Race Gasket Kit - KawasakiFeaturesKit includes a top-of-the line MLSS head gasket and two or more premium-quality base gaskets of different thicknesses to optimize engine compression ratiosGives the rider a choice of using...

Athena - 09345162 - Water Pump Gasket Kit - SuzukiFeaturesKit contents will vary slightly based on applicationSpecsEngine Type2-StrokeProduct NameGasket KitUnitsKitTypeWater PumpRiding StyleOff-RoadFitment2007-2015SuzukiRMZ250

Athena - 09031705 - Piston Kit with Gaskets - 76.76 mm - HondaFeaturesThe smooth profile ensures a regular flow and the perfect flame propagationThe piston for 4-stroke Off-Road motorcycles are made by reverse extrusion and produced numerical control...

Athena - 09031704 - Piston Kit with Gaskets - 76.75 mm - HondaFeaturesThe smooth profile ensures a regular flow and the perfect flame propagationThe piston for 4-stroke Off-Road motorcycles are made by reverse extrusion and produced numerical control...

Athena - 09031702 - Piston Kit with Gaskets - 76.75 mm - HondaFeaturesThe smooth profile ensures a regular flow and the perfect flame propagationThe piston for 4-stroke Off-Road motorcycles are made by reverse extrusion and produced numerical control...

Athena - 09031701 - Piston Kit with Gaskets - 76.76 mm - HondaFeaturesThe smooth profile ensures a regular flow and the perfect flame propagationThe piston for 4-stroke Off-Road motorcycles are made by reverse extrusion and produced numerical control...

Athena - 09031700 - Piston Kit with Gaskets - 76.75 mm - HondaFeaturesThe smooth profile ensures a regular flow and the perfect flame propagationThe piston for 4-stroke Off-Road motorcycles are made by reverse extrusion and produced numerical control...

Boyesen - SC21CB - Ignition Cover - Black - Suzuki RM125FeaturesSeals properly, guarding inside of engine from dirt and water and outlasts stock coversBoyesen Factory Covers are cast from the highest grade of aluminum and are strong yet...

Boyesen - SC23B - Ignition Cover - Black - Suzuki RM250FeaturesSeals properly, guarding inside of engine from dirt and water and outlasts stock coversBoyesen Factory Covers are cast from the highest grade of aluminum and are strong yet...

Boyesen - SC03B - Ignition Cover - Black - Honda CR500RFeaturesSeals properly, guarding inside of engine from dirt and water and outlasts stock coversBoyesen Factory Covers are cast from the highest grade of aluminum and are strong yet...

Boyesen - SC02B - Ignition Cover - Black - Honda CR250RFeaturesSeals properly, guarding inside of engine from dirt and water and outlasts stock coversBoyesen Factory Covers are cast from the highest grade of aluminum and are strong yet...

Cylinder Works - 09310272 - Cylinder Kit - Standard Bore - 96.00 mm - HondaFeaturesCylinder kit includes matched Vertex pistons to ensure longevity, performance and reduced engine noiseNickel Silicon Carbide plated for long lifeKit comes complete with...

Cylinder Works - 09342370 - Big Bore Gasket Kit - KTMFeaturesCylinder kit includes matched Vertex pistons to ensure longevity, performance and reduced engine noiseNickel Silicon Carbide plated for long lifeKit comes complete with gaskets, cylinder,...

Cylinder Works - 09310163 - Cylinder - 66.00 mm - HondaFeaturesNickel Silicon Carbide plated for long lifeMade in the U.S.A.Big bore cylinders do not require machine work.Replacement Part for OEM Number(s):12100KSE670,12100KSE671SpecsBore Size...

Boyesen - 09400217 - Ignition Cover - Magnesium - Suzuki RM125FeaturesSeals properly, guarding inside of engine from dirt and water and outlasts stock coversBoyesen Factory Covers are cast from the highest grade of aluminum and are strong yet...

Cylinder Works - 09310279 - Cylinder Kit - Standard Bore - 77.00 mm - YamahaFeaturesCylinder kit includes matched Vertex pistons to ensure longevity, performance and reduced engine noiseNickel Silicon Carbide plated for long lifeKit comes complete with...

Cylinder Works - 09310274 - Cylinder Kit - Standard Bore - 96.00 mm - HondaFeaturesCylinder kit includes matched Vertex pistons to ensure longevity, performance and reduced engine noiseNickel Silicon Carbide plated for long lifeKit comes complete with...

Cylinder Works - 09310276 - Cylinder Kit - Standard Bore - 77.00 mm - KawasakiFeaturesCylinder kit includes matched Vertex pistons to ensure longevity, performance and reduced engine noiseNickel Silicon Carbide plated for long lifeKit comes complete with...

Cylinder Works - 09310120 - Cylinder Kit - Big Bore - 80.00 mm - Kawasaki | SuzukiFeaturesCylinders have a nickel silicon carbide cylinder sleeveLook virtually identical to OEM cylindersKit includes cylinder, pistons, rings, pin, clips and gasketsMade in...

Cylinder Works - 09310174 - Cylinder Kit - Big Bore - 98.00 mm - YamahaFeaturesCylinders have a nickel silicon carbide cylinder sleeveLook virtually identical to OEM cylindersKit includes cylinder, pistons, rings, pin, clips and gasketsMade in the...

Boyesen - 09400564 - Clutch Cover - Black - HondaFeaturesLightweight factory clutch covers provide years of outstanding protection; guaranteed not to warpIndividually surfaced for a perfect, leak-free fitSuper-tough, powder-coated finish resists...

Boyesen - 09400396 - Clutch Cover - Magnesium - YamahaFeaturesLightweight factory clutch covers provide years of outstanding protection; guaranteed not to warpIndividually surfaced for a perfect, leak-free fitSuper-tough, powder-coated finish resists...

Boyesen - 09400239 - Clutch Cover - Magnesium - YamahaFeaturesLightweight factory clutch covers provide years of outstanding protection; guaranteed not to warpIndividually surfaced for a perfect, leak-free fitSuper-tough, powder-coated finish resists...

Boyesen - 09400210 - Ignition Cover - Magnesium - Honda CR250RFeaturesSeals properly, guarding inside of engine from dirt and water and outlasts stock coversBoyesen Factory Covers are cast from the highest grade of aluminum and are strong yet...

Boyesen - 09400696 - Ignition Cover - Black - Husqvarna/KTMFeaturesSeals properly, guarding inside of engine from dirt and water and outlasts stock coversBoyesen Factory Covers are cast from the highest grade of aluminum and are strong yet...

Boyesen - 09400222 - Clutch Cover - Magnesium - HondaFeaturesLightweight factory clutch covers provide years of outstanding protection; guaranteed not to warpIndividually surfaced for a perfect, leak-free fitSuper-tough, powder-coated finish resists...

Boyesen - 09400212 - Ignition Cover - Magnesium - Honda CR500RFeaturesSeals properly, guarding inside of engine from dirt and water and outlasts stock coversBoyesen Factory Covers are cast from the highest grade of aluminum and are strong yet...

Boyesen - 09400215 - Ignition Cover - Magnesium - Kawasaki KX250FeaturesSeals properly, guarding inside of engine from dirt and water and outlasts stock coversBoyesen Factory Covers are cast from the highest grade of aluminum and are strong yet...

Boyesen - 09400220 - Ignition Cover - Magnesium - Yamaha YZ 250/YZ 250 XFeaturesSeals properly, guarding inside of engine from dirt and water and outlasts stock coversBoyesen Factory Covers are cast from the highest grade of aluminum and are strong yet...

Boyesen - 09400218 - Ignition Cover - Magnesium - Suzuki RM250FeaturesSeals properly, guarding inside of engine from dirt and water and outlasts stock coversBoyesen Factory Covers are cast from the highest grade of aluminum and are strong yet...

Boyesen - 09400214 - Ignition Cover - Magnesium - Kawasaki KX125FeaturesSeals properly, guarding inside of engine from dirt and water and outlasts stock coversBoyesen Factory Covers are cast from the highest grade of aluminum and are strong yet...

Boyesen - 09400705 - Clutch Cover - Black - KTMFeaturesLightweight factory clutch covers provide years of outstanding protection; guaranteed not to warpIndividually surfaced for a perfect, leak-free fitSuper-tough, powder-coated finish resists weathering...

Boyesen - 09400706 - Clutch Cover - Magnesium - KTMFeaturesLightweight factory clutch covers provide years of outstanding protection; guaranteed not to warpIndividually surfaced for a perfect, leak-free fitSuper-tough, powder-coated finish resists...

Boyesen - 09400693 - Clutch Cover - Black - Husqvarna/KTMFeaturesLightweight factory clutch covers provide years of outstanding protection; guaranteed not to warpIndividually surfaced for a perfect, leak-free fitSuper-tough, powder-coated finish resists...

Boyesen - 09400238 - Clutch Cover - Black - YamahaFeaturesLightweight factory clutch covers provide years of outstanding protection; guaranteed not to warpIndividually surfaced for a perfect, leak-free fitSuper-tough, powder-coated finish resists...

Boyesen - 09400395 - Clutch Cover - Black - YamahaFeaturesLightweight factory clutch covers provide years of outstanding protection; guaranteed not to warpIndividually surfaced for a perfect, leak-free fitSuper-tough, powder-coated finish resists...

Boyesen - 09400565 - Clutch Cover - Magnesium - HondaFeaturesLightweight factory clutch covers provide years of outstanding protection; guaranteed not to warpIndividually surfaced for a perfect, leak-free fitSuper-tough, powder-coated finish resists...

Boyesen - 09400445 - Clutch Cover - Black - Kawasaki/SuzukiFeaturesLightweight factory clutch covers provide years of outstanding protection; guaranteed not to warpIndividually surfaced for a perfect, leak-free fitSuper-tough, powder-coated finish...

Boyesen - 09400393 - Clutch Cover - Magnesium - YamahaFeaturesLightweight factory clutch covers provide years of outstanding protection; guaranteed not to warpIndividually surfaced for a perfect, leak-free fitSuper-tough, powder-coated finish resists...