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Performance Disc Muffler
Removable discs to adjust for sound and performance.
Forest Approved spark arrestor also
 Clamps on or weld on  1 5/16  and   2”  ID.
 
These mufflers use a series of discs to control the exhaust flow and sound of your vehicle. By adding or removing discs, you can adjust the backpressure, which affects the powerband and exhaust tone. This allows for a customizable riding or driving experience, whether the muffler is for your gokart, mini bike, mud boat or generator.
 
Advantages of Disc Muffler for small engine power.
 
  • Tunability: You can adjust the number of discs to fine-tune the exhaust flow, which allows you to optimize the engine's powerband and performance. Adding discs increases exhaust flow and top-end power, while removing discs increases low-end torque1.
  • Noise Reduction: The design of disc mufflers helps to reduce exhaust noise significantly. This is particularly beneficial for small engines used in residential areas or for equipment like lawn mowers and generators2.
  • Spark Arrestor: Many disc mufflers are designed to function as spark arrestors, which helps prevent hot exhaust sparks from escaping and potentially causing fires. This is especially important for off-road vehicles and equipment used in dry or forested areas1.
  • Lightweight and Compact: Disc mufflers are generally smaller and lighter compared to traditional mufflers, which can help reduce the overall weight of the equipment and improve handling.
  • Scavenging Effect: The gap between the discs creates a scavenging effect, which helps to improve the efficiency of the exhaust system by reducing backpressure and allowing for better expulsion of exhaust gases.
Would you like to know more about how to install or adjust these mufflers?
Great! Here's a step-by-step guide on how to install and adjust a disc muffler for small engines:
Installation:
  • Safety First: Ensure the engine is off and cool before starting the installation to avoid burns or injuries.
  • Remove the Old Muffler: If there's an existing muffler, use the appropriate tools (usually a wrench) to remove it. Keep the bolts and gaskets as you may need them for the new installation.
  • Prepare the Mounting Surface: Clean the exhaust port and surrounding area to ensure a proper seal and fit for the new muffler.
  • Attach the Disc Muffler: Position the new disc muffler against the exhaust port. Use the bolts and gaskets from the old muffler or the ones provided with the new muffler to secure it in place. Tighten the bolts evenly to ensure a good seal.
Adjustment:
  • Start with a Baseline: Install a standard number of discs (e.g., 6-8 discs) to start with a middle-ground setting.
  • Fine-Tuning: Start the engine and let it warm up. Observe the performance and exhaust sound.
  • Increase Discs: If you want more top-end power and a louder exhaust note, add more discs. Each disc increases the exhaust flow.
  • Decrease Discs: If you want more low-end torque and a quieter exhaust, remove some discs. This increases backpressure and enhances torque at lower RPMs.
  • Check Performance: Test the engine after each adjustment to find the optimal number of discs that provide the best performance for your specific needs.
Maintenance:
  • Regularly check the condition of the discs and bolts. Tighten any loose bolts and replace damaged discs to ensure the muffler operates efficiently.
  • Clean the discs periodically to prevent clogging and maintain optimal exhaust flow.
By following these steps, you can ensure your small engine is running smoothly and efficiently with a disc muffler. If you have any more questions or need further assistance, feel free to ask!
By adding or removing discs, you can adjust the backpressure, which affects the powerband and exhaust tone. This allows for a customizable riding or driving experience

Disc Muffler

SKU: DM
$46.75Price

     (605)545-0424

    (605)787-5676

    ​

    8am to 5pm  MST

    Monday-Friday

    We do not offer on line ordering at this time,

    due to the complexity of our products​

    ​

    Mailing Address: 

    6940 Harley Lane

    Rapid City, SD 57702

    ​​

    Get Map to Our Shop


    ©2024 by Mrken777 Productions

     

     

    Exhaust Systems for Predator 420cc: There are various options for exhaust headers and systems designed for the Predator 420cc engine, useful for go-karts, mini bikes, and other applications. These systems aim to improve performance by enhancing exhaust flow. Custom Exhaust Kits: You can find custom exhaust flanges and headers specifically made for the Predator 420cc from Harbor Freight, which are suited for building custom exhaust setups for generators, go-karts, or mini bikes. Performance Considerations: Custom exhausts can significantly affect the performance of your engine. The right exhaust system can optimize power output by improving airflow. However, there's a discussion around the correct sizing of exhaust pipes to match engine displacement and the desired RPM range for optimal performance. Installation and Compatibility: Ensure any exhaust you consider is compatible with your specific model. Some modifications might be required, like re-jetting or carburetor tuning, especially if you're going for a high-performance setup.

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    Mini Bikes:

    Design and Use:

    • Mini bikes are small, lightweight motorcycles typically used for recreation, off-road racing, or as a fun, economical means of transportation. They come in various designs, from simple frames with basic control systems to more sophisticated models with suspension systems, better brakes, and more powerful engines.

     

    Performance and Customization:

    • Mini bikes are highly customizable. Enthusiasts often modify them for better performance, which includes upgrading engines, exhaust systems, suspension, and tires. The community around mini bikes is vibrant, with many forums and groups dedicated to sharing tips, tricks, and builds.

     

    Safety and Legalities:

    • While fun, mini bikes can be dangerous if not used responsibly. Helmets, protective gear, and understanding local laws regarding where and how they can be ridden are crucial. Many places have regulations on engine size, noise levels, and where these bikes can be operated.

     

    Predator 420cc Engine:

    Engine Specifications:

    • The Predator 420cc is a 13 horsepower, OHV (Overhead Valve), air-cooled, four-stroke engine from Harbor Freight. Known for its durability and ease of modification, it's a popular choice for applications like mini bikes, go-karts, and even modified bicycles.

     

    Performance Modifications:

    • Carburetor Tuning: The Predator 420 often requires carburetor adjustments or upgrades for optimal performance, especially when paired with a high-flow exhaust. Discussions on forums like Reddit suggest that a 34mm Mikuni carb might be too large for some setups, recommending smaller options like a 26mm for better tuning.

       

    • Exhaust Systems: Performance headers or custom exhaust setups can significantly increase power by improving exhaust flow. Options range from simple headers to full race exhausts, often discussed in terms of noise, power gain, and heat management.

       

    • Governor Removal: Many remove the governor for higher speeds, but this comes with the responsibility of ensuring the bike or kart can handle the increased power without safety issues.

    • Clutches and Transmissions: For mini bikes or go-karts, choosing the right clutch or even a small transmission can be key. Torque converters or centrifugal clutches are common, with specific setups like the 40 series torque converter being noted for the Predator 420.

       

     

    Frame and Structural Considerations:

    • Fitting a 420cc engine into a mini bike frame often requires significant modifications. The engine's size and weight might necessitate reinforcing the frame or even custom-building parts to ensure structural integrity and correct chain alignment.

       

     

    Community and Resources:

    • The Predator 420 has a strong following in the DIY and motorsport communities. Websites like GoKartsUSA and forums like MiniRiders offer parts, advice, and community support. Builders share everything from basic setups to high-performance modifications, including how to manage the high torque and power of the 420cc engine in a smaller, less stable vehicle.

       

       

     

    Safety and Maintenance:

    • With any high-performance modification, safety becomes paramount. Regular maintenance, especially on the engine, brakes, and frame, is crucial to prevent accidents or breakdowns. This includes checking for wear on chains, ensuring proper lubrication, and tuning the engine to avoid running too lean or rich.

     

    This information should give you a good overview of integrating the Predator 420cc into mini bikes, highlighting both the potential for performance and the challenges of safety and compatibility.

    Predator 420cc modifications

    Mini bike racing events

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