The exhaust system plays a crucial role in engine performance by efficiently expelling burnt gases. On Coleman mini bikes like the CT200U, the exhaust uses a simple head pipe and muffler design. In this article, we’ll discuss exhaust system operation, aftermarket upgrades for increased power, as well as inspection and maintenance best practices.
How the Exhaust System Works
The mini bike exhaust system consists of several key components working in tandem:
- Head pipe – Connects to the cylinder head and carries hot exhaust gases toward the muffler. Size and length affect power.
- Muffler – Chambers absorb noise while allowing gases to pass. Mini bikes use simple expansion chamber mufflers.
- Spark arrestor – A screen assembly prevents flammable debris from exiting and causing fire. Required on off-road machines.
- Gaskets – Seals between joints prevent exhaust leaks which decrease performance and raise noise.
- O2 sensor – Monitors oxygen content to provide feedback for fuel mapping and emission control (on fuel injected models).
As rapidly expanding gases exit the combustion chamber, the exhaust system efficiently carries them away while controlling noise. Proper design optimize power production.
Reasons to Upgrade Your Exhaust
The stock exhaust on most production mini bikes like the Coleman CT200U is extremely restrictive to meet sound and emissions regulations. An aftermarket exhaust provides huge performance benefits:
- Increased diameter head pipe improves flow for less pumping loss.
- Reduces backpressure which inhibits the engine’s ability to expel spent gases.
- Allows the engine to breathe better and realize its full power potential.
- Adds 2-3 HP to the engine’s output across the entire RPM range.
- Provides a much more aggressive exhaust note which many riders prefer.
For maximum power from engine modifications like big bore kits or cams, an aftermarket exhaust is essential to reduce restriction.
Improved Exhaust System Designs
Factory exhausts focus on quiet operation rather than peak power. Aftermarket systems use improved designs:
- Stepped head pipe provides optimized diameter and backpressure at different RPMs.
- Merge collector joins dual front head pipes into a single rear pipe. Improves scavenging.
- Low restriction muffler core lets gases pass freely while controlling noise.
- Tip shape and orientation optimizes exhaust exit direction.
- Lightweight aluminum or titanium alloys vs. heavy steel factory parts.
- High quality stainless steel resists corrosion and prevents power loss.
Aftermarket companies invest significant R&D into exhaust system design for maximum power gains without excessive noise.
Exhaust Upgrade Options for Coleman Mini Bikes
Many exhaust brands offer improved performance and sound for your Coleman:
- Xtreme Motor – Great value exhausts in various diameters with aluminum mufflers. Bolt-on fitment.
- Shredder Parts – Stepped pipes and low restriction cores give big gains. Quieter than some.
- Manco – Aggressive exhaust notes with quality cast mufflers. Good for big bore builds.
- GoPowerSports – Affordable slip-ons that still outflow stock and sound great.
- Stage6 Racing – Lightweight titanium or carbon fiber systems for maximum flow and minimum weight.
With so many options, pick an exhaust that delivers the sound and performance you desire. Any quality aftermarket system outflows stock for a huge improvement.
Installation Tips and Requirements
When installing your new exhaust system, follow these guidelines:
- Use a high temp exhaust gasket sealant on all mating surfaces. This prevents leaks. Allow proper curing time before riding.
- Attach all springs and mounts securely using factory torques specs. Check for adequate clearance around pipes.
- On some models, an exhaust flange adaptor is required to mate the new head pipe to the cylinder.
- Always include the spark arrestor to prevent fire danger and meet off-road requirements.
- Retighten clamps after the initial ride as pipes expand. This prevents loss of power and noise increase over time.
With proper installation using quality gaskets, your new exhaust will perform reliably for years while giving your Coleman mini bike a very noticeable bump in power.
Exhaust Maintenance Best Practices
To keep your exhaust in peak operating condition:
- Hand wash pipes to remove dirt before it bakes on. Avoid harsh chemical cleaners.
- Use high-temp paint to touch up any chrome or finish damage to prevent corrosion.
- Check mounting points, springs and clamps. Tighten or replace deteriorated parts.
- Inspect gaskets and o-rings for leakage that impacts power and raises noise.
- Clean spark arrestor screen regularly to prevent clogging which causes loss of power.
- Monitor pipe location and sagging that could lead to contact with plastics or rider.
- listen for rattling internal muffler baffles that indicate a failing core needing replacement.
Well-maintained pipes stay secure, minimize noise, and allow your engine to produce maximum horsepower season after season.
Troubleshooting Exhaust Problems
Be alert for any of these common exhaust-related problems:
Loss of power – Can indicate a clogged spark arrestor screen, crimped pipes, exhaust leak allowing air in, or blown out muffler core.
Visible exhaust smoke – Blue smoke generally indicates oil burning from worn piston rings or valve guides. Black smoke means a rich fuel mixture.
Excess noise – Often a result of exhaust leak from damaged gasket or loose clamp. Rattling muffler core or missing baffles causes harshness.
Discoloration of pipes – Normal for pipes to turn dull blue after use from heat. But excessive corrosion indicates damaged finish.
Address any exhaust issues promptly to maximize performance and avoid more significant damage long term.
Exhaust System Do’s and Don’ts
Here are some key guidelines when operating your mini bike with an aftermarket exhaust:
DO:
- Stay on designated off-road areas to avoid noise complaints.
- Make sure you have proper clearance from plastics and controls.
- Let pipes fully cool before washing or covering to prevent burns or heat damage.
DO NOT:
- Exceed recreational riding time limits in local areas and trails.
- Modify exhaust for intake or performance without considering noise impact.
- Ride immediately after installation before gaskets fully cure.
While aftermarket exhausts provide a big performance gain, be responsible to avoid hassles. Most importantly, properly maintain your exhaust system.
Get the Most From Your Engine
We hope this guide has improved your knowledge of how the exhaust system works to expel burnt gases as efficiently as possible. A less restrictive aftermarket design allows your engine to reach its true potential.
But be sure to tune your carburetor and airbox to complement the increased airflow. Match your exhaust choice to your mini bike model and performance build goals. And remember to inspect and care for your pipes to maximize durability.
At Coleman Powersports, we want you to get the most enjoyment and life from your mini bike without compromising power. Contact our tech support team if you need any guidance selecting and installing the best exhaust system for your ride. Your engine will thank you!
