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Main Jet Performance Upgrade Kit For GX390 and Predator 420cc Main Jet Performance Upgrade Kit For GX390 and Predator 420cc

Our main jet kit is a must for the Honda GX390, Predator 420cc engines that have had the performance K&N style air filter setup installed on the engine. Maximizes the engine for best performance and air fuel ratio.

Our Price: $8.14
Bullfrog Pro Velocity High Performance Air Filter Kit for Honda GX390 Bullfrog Pro Velocity High Performance Air Filter Kit for Honda GX390

Our Pro Velocity high performance air filter kit fits Honda GX340, GX390, Predator 420cc and 460cc big block clone engines. Upgrade your go kart, mini bike or drift trike with our high performance air filter kit. Our kit includes the following items:


  • High flow racing style air filter 4" filter length
  • Foam Pre-Filter
  • Radiused air filter adapter
  • Choke hold bracket

Our Price: $44.95
GX390 Big Block Bored Carburetor 23.5mm Venturi GX390 Big Block Bored Carburetor 23.5mm Venturi

Bullfrog Performance Products big block bored performance carburetor.  Our carburetor is CNC bored to obtain consistant max air flow.  Our carb has extensive carb air horn modifications along with the fuel circuits re-worked for the best transient and wide open throttle use.  Select if you need gas or methanol / alky fuel.

List Price: $171.35
Our Price: $149.00
Savings: $22.35