Crankcase Reed: Remove the reed cage and see if cylinder sleeve blocks airflow? Does the reed stopper cover the Boost Port? (Needs Reed Spacer) Is there a smooth transition from the reeds to the base of transfer ports? Cylinder Reed: Check for reed stopper covering Boost Port? Can the air move freely under the piston and around it to the sides? Piston Port: Is the intake tract open and smooth for maximum flow?

Is your exhaust port big enough for the pipes at a specific rpm? Is there enough TimeArea (TA) for the compression and rpm? Is there enough BlowDown? (Time between Exhaust port opening and Transfer ports opening.)

Here is where the computer is a great tool to help get port timing right for the most power. The TSR software calculates TA based on BMEP (See BMEP Page). The exhaust port designed by the computer is mapped out, and then cut into the cylinder. The port is smoothed, polished, and the exhaust flange matched. Increasing the airflow from carb boot thru to the exhaust flange provides the most useable gains in Torque and HP.

Each part of the 2-stroke cycle can be evaluated and designed. Computer input requirements are indicated for the following TSR software programs:

Exhaust & Transfer Ports - TimeArea & BlowDown TA - Input Required: BMEP & RPM + Degree Wheel requirements.

Degree Wheel - Input Required: Bore, Stroke, Con Rod Length & Piston Pin Offset.

Pipes - Input Required: Exh. & Trans. Port Openings, Degree Wheel Info + RPM & Pipe Temperature.

Heads - Maximum Squish Velocity (MSV) - Input Required: Degree Wheel info + Compression Ratio, Head CC’s, and Squish Band measurements.

Boost Bottle - Input Required: Bore & Stroke, # of Cylinders, RPM that Pipe Starts to Work.

Set Reed Stopper Height & Curve / Radius - Input Required: ALL Measurements from Reed & Cage.

The TSR Programs make it easy to compare Big Bore variables, and find where the limits are, for a specific rpm and compression. Then modify or design a tuned pipe.