The Rhine West Performance software for “R” series motorcycles is tuned around two types of exhaust systems: the “high back-pressure” version and the “free-flow” version.

The “high back-pressure” versions includes the stock exhaust system, and various aftermarket manufacturers. Typically any exhaust system that uses a diversionary baffle system, increases the pressure on the exhaust gasses and should run on the stock exhaust system setting. This tuning map is accessed by having the stock coding plug for the motorcycle installed.

The “free-flow system” is any exhaust system that would be considered “free-flow” or a “straight pipe”. This tuning map is accessed by removing the coding plug from the motorcycle.

The coding plug determines various tuning maps that the control unit uses to run the engine. By removing or installing the stock coding plug, the owner can switch between maps tuned for “free-flow” exhausts systems or “high back-pressure” exhaust systems.

We have seen some coding plugs that are modified from the stock condition, meaning that the internal jumpers have been cut inside the coding plug. To check the coding plug, simply find the resistance between the pins of the coding plug. If the coding plug is properly configured all pins should be a closed circuit to one another.

Each U.S. specification motorcycle was delivered with a particular coding plug installed. The chip is designed to run with this coding plug in place when the high back-pressure exhaust system is installed on the motorcycle. To determine the correct coding plug for your motorcycle see the chart below.