Honda TRX400EX
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With less than 30HP stock, the 400EX is in need of some major power improvements. The EX has plenty of low-end torque, but needs more midrange and top-end pwerformance. Our Race Grind camshaft gives a nice power increase up top and combined with our head modifications, gets the 400EX to a respectful level. Check out the details below on these power products for the Honda TRX400EX.
Performance Products
Exhaust System: Increase throttle response and acceleration with an LRD Full exhaust system. Produces a 3HP increase @ 3000RPM and a 6HP gain @ 9000RPM.
Camshaft : Our Race Grind Cam significantly increase mid and top-end performance. Run the Titanium Valve Spring kit and HD Rocker Arms for Reliability.
High-Compression Piston: For more acceleration, install a 10.5 or 12.0:1 JE Piston. Each of these pistons incorporates additional strength, durability and weight reduction, in addition to the power properties.
Carburetor Kit : We have developed the ultimate carb kits. For machines without porting, we recommend the 39MM Keihin FCR. It's smooth bore design improves airflow over stock and the accelerator pump increases low RPM throttle response. For modified motors, go with the 41MM FCR. We include a matching throttle cable.
Performance Services
Head Modification : We port and flow the cylinder head for maximum velocity and more CFM. We cut the valve seats at multiple angles and blend them into the intake port for smooth transitioning around the valve.
Cylinder Re-Sleeve: We can set your EX up with 87MM (415cc), 88MM (425cc), & 89MM (435cc) sleeves for increases in displacement. We utilize torque-plates to ensure no cylinder warpage occurs during the process.
