Athena 400cc Cylinder Kit Bolt on kit, no machining required Aluminum cylinder with nickel-carbide coating designed with wider water jackets Complete piston kit, Forged piston with molybdenum coating Complete top end gasket set Easy to follow step-by-step installation instructions Average power gains of 3hp can be seen in most models This Kit has 12.2:1 Compression

Athena 450cc Cylinder Kit Bolt on kit, no machining required Aluminum cylinder with nickel-carbide coating designed with wider water jackets Complete piston kit, Forged piston with molybdenum coating Complete top end gasket set Easy to follow step-by-step installation instructions Average power gains of 3hp can be seen in most models Compression ratios are as follows CRF450R/X Kit has 11.5:1 YZ/WR450F Kit has 12.3:1 TRX450R Kit has 10.5:1 LT-R450 Kit has 11.7:1 YFZ450 Kit has 11.9:1

Athena 250cc Cylinder Kit Bolt on kit, no machining required Aluminum cylinder with nickel-carbide coating designed with wider water jackets Complete piston kit, Forged piston with molybdenum coating Complete top end gasket set Easy to follow step-by-step installation instructions Average power gains of 2hp can be seen in most models Compression ratios are as follows CRF250R/X Kit has 13.0:1 KX250F/RMZ250 Kit has 12.6:1 YZ/WR250F Kit has 12.5:1 Note: Images are for reference only; Images may not show your specific cylinder kit.

Complete system with titanium MegaBomb header and midpipe. Race proven reliability testing, high temp multi-layer packing material and exclusive repack maintenance indicator. Features: The lightest full system available Natural or Anodized Blue Titanium Silencer Superior power and performance - horsepower improved throughout RPM range Features exclusive proprietary Chamber Core and MegaBomb technology Factory Forward Engineering centralizes mass, improves handling Titanium muffler with titanium endcaps, midpipe and MegaBomb header Made from premium quality American materials MegaBomb header effectively reduces sound output by as much as 1.5dB while providing the low end of a long header and the top end of a short header Performance tuning inserts and spark arrestor module available Meets AMA sound requirements on most models; inserts available for others Click Here for Additional Exhaust Information

Pro Circuit exhaust systems for four-stroke engines are the top choice of ATV riders today. The product of state-of-the-art technology and extensive real-world testing, the Pro Circuit four-stroke exhaust systems boost over-all performance with explosive bottom, mid-range and peak power. Because they're constructed to withstand even the most abusive conditions, these systems are sure to give you years of unrivaled performance off-road or on the track. Features: Revolutionary new system uses a longer aluminum body and special internal E-glass packing to lower noise output to legal dB without sacrificing power Produces an impressive gain in horsepower when compared to OEM Stainless steel intake tube and FIM-approved end cap Lightweight aluminum mounting brackets Wire-mesh, removable spark arrester Modular end caps for tunable power Click Here for Additional Exhaust Information

The Akrapovic RACING system is designed for riders who know who to take full advantage of the specific performance benefits offered by these systems. We should especially mention the new Akrapovic HEXAGONAL design muffler, which with its carbon-fiber outlet cap goes exceptionally well with the design of the modern motorcycles. System features header tube, link pipe and muffler. All parts are connected with CNC machined sleeves for perfect fit and secured with silicone shielded springs. Racing line system only differs from our top line Evolution Line system in material, as we use stainless steel for header tube and link pipe. Muffler is equal to Evolution system, therefore its outer sleeve is available either in carbon fiber or titanium. simple mounting excellent upgrade in performance deep sound hexagonal shape muffler eye-catching product which significantly changes the appearance of the bike improved engine characteristics: more power and torque in comparison with the stock muffler and competing products high quality and exotic materials: combination of carbon-fiber, titanium and stainles steel precision workmanship choice of carbon-fiber or titanium muffler outer sleeve Click Here for Additional Exhaust Information

The Akrapovic RACING system is designed for riders who know who to take full advantage of the specific performance benefits offered by these systems. We should especially mention the new Akrapovic HEXAGONAL design muffler, which with its carbon-fiber outlet cap goes exceptionally well with the design of the modern motorcycles. System features header tube, link pipe and muffler. All parts are connected with CNC machined sleeves for perfect fit and secured with silicone shielded springs. Racing line system only differs from our top line Evolution Line system in material, as we use stainless steel for header tube and link pipe. Muffler is equal to Evolution system, therefore its outer sleeve is available either in carbon fiber or titanium. simple mounting excellent upgrade in performance deep sound hexagonal shape muffler eye-catching product which significantly changes the appearance of the bike improved engine characteristics: more power and torque in comparison with the stock muffler and competing products high quality and exotic materials: combination of carbon-fiber, titanium and stainles steel precision workmanship choice of carbon-fiber or titanium muffler outer sleeve Click Here for Additional Exhaust Information

The Bell Star Viper has been engineered form the ground up over a period of three years, the Star is simply the best Bell ever. And that?s saying a lot considering Bell invented the motorcycle helmet. Features and Benefits Crafted out of Bell?s super lightweight Kevlar/Carbon Fiber/Fiberglass TriMatrix Composite and is sculpted into a wind tunnel-proven, super stable, lift-free design Equipped with Velocity Flow Ventilation with FlowAdjust, a revolutionary airflow management system keeping the rider?s head cool and dry Super stable aerodynamic signature designed to enhance stability and resist lift Comes with Track Strip for track days, an add-on wicker that further improves stability at high speeds 3Mode Shield with ClickRelease is the easiest shield to use and change NutraFog II coated shield to virtually eliminate fogging Contour Cut Cheek pads for superior fit and comfort Certification: Snell M2005, DOT Weight: 1550g

The Bell Star Viper has been engineered form the ground up over a period of three years, the Star is simply the best Bell ever. And that?s saying a lot considering Bell invented the motorcycle helmet. Features and Benefits Crafted out of Bell?s super lightweight Kevlar/Carbon Fiber/Fiberglass TriMatrix Composite and is sculpted into a wind tunnel-proven, super stable, lift-free design Equipped with Velocity Flow Ventilation with FlowAdjust, a revolutionary airflow management system keeping the rider?s head cool and dry Super stable aerodynamic signature designed to enhance stability and resist lift Comes with Track Strip for track days, an add-on wicker that further improves stability at high speeds 3Mode Shield with ClickRelease is the easiest shield to use and change NutraFog II coated shield to virtually eliminate fogging Contour Cut Cheek pads for superior fit and comfort Certification: Snell M2005, DOT Weight: 1550g

The Bell Star Viper has been engineered form the ground up over a period of three years, the Star is simply the best Bell ever. And that?s saying a lot considering Bell invented the motorcycle helmet. Features and Benefits Crafted out of Bell?s super lightweight Kevlar/Carbon Fiber/Fiberglass TriMatrix Composite and is sculpted into a wind tunnel-proven, super stable, lift-free design Equipped with Velocity Flow Ventilation with FlowAdjust, a revolutionary airflow management system keeping the rider?s head cool and dry Super stable aerodynamic signature designed to enhance stability and resist lift Comes with Track Strip for track days, an add-on wicker that further improves stability at high speeds 3Mode Shield with ClickRelease is the easiest shield to use and change NutraFog II coated shield to virtually eliminate fogging Contour Cut Cheek pads for superior fit and comfort Certification: Snell M2005, DOT Weight: 1550g

The Bell Star Viper has been engineered form the ground up over a period of three years, the Star is simply the best Bell ever. And that?s saying a lot considering Bell invented the motorcycle helmet. Features and Benefits Crafted out of Bell?s super lightweight Kevlar/Carbon Fiber/Fiberglass TriMatrix Composite and is sculpted into a wind tunnel-proven, super stable, lift-free design Equipped with Velocity Flow Ventilation with FlowAdjust, a revolutionary airflow management system keeping the rider?s head cool and dry Super stable aerodynamic signature designed to enhance stability and resist lift Comes with Track Strip for track days, an add-on wicker that further improves stability at high speeds 3Mode Shield with ClickRelease is the easiest shield to use and change NutraFog II coated shield to virtually eliminate fogging Contour Cut Cheek pads for superior fit and comfort Certification: Snell M2005, DOT Weight: 1550g

The Bell Star Viper has been engineered form the ground up over a period of three years, the Star is simply the best Bell ever. And that?s saying a lot considering Bell invented the motorcycle helmet. Features and Benefits Crafted out of Bell?s super lightweight Kevlar/Carbon Fiber/Fiberglass TriMatrix Composite and is sculpted into a wind tunnel-proven, super stable, lift-free design Equipped with Velocity Flow Ventilation with FlowAdjust, a revolutionary airflow management system keeping the rider?s head cool and dry Super stable aerodynamic signature designed to enhance stability and resist lift Comes with Track Strip for track days, an add-on wicker that further improves stability at high speeds 3Mode Shield with ClickRelease is the easiest shield to use and change NutraFog II coated shield to virtually eliminate fogging Contour Cut Cheek pads for superior fit and comfort Certification: Snell M2005, DOT Weight: 1550g