Professional Two Stroke Cylinder Porting Services
Ken OConnor Racing provides professional two stroke cylinder porting for motorcycle, ATV and other powersports engines. With decades of hands-on porting and engine-building experience, we tailor each cylinder’s port timing, shape and flow characteristics to the engine, supporting components and intended type of riding. Our goal is usable performance—not simply making the ports larger.
Porting 2 Stroke Engines
Custom Porting for Two Stroke Performance
Many components affect the power delivery of a two stroke engine, including the exhaust pipe, silencer, carburetor, reeds, intake system and power valve. These bolt-on modifications can be extremely effective when properly matched to the engine.
Cylinder porting is different. Once material is removed or port timing is changed, the cylinder cannot simply be returned to its original configuration. Successful porting requires accurate measurement, specialized equipment and a thorough understanding of airflow, charge velocity and two stroke port timing.
Why Proper Cylinder Porting Matters
Modern cylinder castings can already be highly efficient. Simply enlarging the ports does not guarantee more power. Excessive grinding can reduce charge velocity, weaken low-speed performance or permanently damage the cylinder.
Professional two stroke cylinder porting may involve carefully modifying port timing, port shape, directional flow and transitions. Every change influences where and how the engine produces power.
Ken OConnor Racing develops a porting specification around the complete engine combination and its intended use. The objective is a controlled, usable power increase matched to the rider and machine.
Our Two Stroke Porting Services
Our cylinder porting work can include:
- Inspection and measurement of the cylinder
- Evaluation of the existing port layout
- Correction of casting imperfections
- Modification of port timing when appropriate
- Reshaping and blending port transitions
- Matching the cylinder to the engine combination
- Final inspection before return shipping
Porting recommendations are based on the engine, exhaust system, carburetor, reeds, displacement and desired power delivery.
Experience You Can Trust
Ken OConnor Racing has been porting high-performance two stroke cylinders for decades. We were also among the first professional engine builders to share cylinder-porting techniques and technical information through YouTube and online enthusiast communities.
Our experience includes complete engine machining and rebuilding—not just cylinder grinding. This allows us to evaluate how cylinder porting works with compression, bore condition, crankshaft condition and the rest of the engine combination.
Two Stroke Cylinder Porting Prices
| Porting 2 Stroke Cylinders | |
| 2 Stroke Cylinder Porting | $220-$350 |
| Power Valve Service includes parts cleaning, installation and adjustment | $95 |
What information do you need before porting my cylinder?
We need to know the machine, engine size, intended use, exhaust system, carburetor, reeds and the type of power delivery you want. Information about any previous engine modifications is also helpful.
Does cylinder porting always increase horsepower?
Correctly designed porting can improve engine performance, but larger ports do not automatically produce more power. Port timing, port shape, charge velocity and the complete engine combination must work together.
Can you port a cylinder for trail riding?
Yes. Porting can be designed for different performance goals, including stronger low- and midrange power, broad recreational power or higher-RPM competition use.
Do you service power valves?
Yes. Power valve service is available and includes cleaning, installation and adjustment.
ship my cylinder to Ken OConnor Racing
We ship and receive worldwide daily.
Most jobs ship in less than ten days!