What is a Power Commander?
The PC is a fuel injection and ignition timing (on some models) adjustment unit that plugs "inline" with the bikes' stock ECU. The PC uses original equipment style connectors so that no splicing or cutting of the harness is required. Most installations take less than 15 minutes, some as little as 5 minutes. Changes are made to the bikes fuel and ignition curves via the PC's onboard microprocessor. Using this technology we are able to offer a large area of adjustment without making any permanent changes to the bikes' ECU (electronic control unit). Removing the PC returns the bike to its previous stock condition. The Power Commander can be ordered preprogrammed with a your choice of several settings, based on the modifications to your bike. The unit also comes complete with software and cable link that allows you to change between different maps or make adjustments to a map file.
How much power gain?
"The perfect air/fuel ratio will ensure that the engine can produce the maximum possible horsepower for that given combination". A typical street rider spends a great deal of time riding in part throttle conditions. Shown below are two graphs of a motorcycle before and after installation of the Power Commander . The top graph shows the horsepower curve accelerating at a 40% throttle opening and the lower graph shows the corresponding air / fuel ratio. You can see a large horsepower increase between the two. The red curve shows a typical stock motorcycle with minor performance modifications (slip-on exhaust). The blue curve shows that same combination with the PC installed and you can see that the line is nearly straight. So the rider will feel a large improvement while riding the motorcycle and it is very possible that the peak wide open throttle horsepower is unchanged. The correct air/fuel ratio number (say 12.9:1 or 13.2:1) depends upon many factors like combustion chamber design but what we want is that figure at every point in the curve (straight line).
The original Power Commander was introduced in 1997 and was available for the Suzuki TL1000S, TL1000R and 98 GSXR750. This Power Commander offered "Fuel Only" adjustment and proved very successful. Only a limited number of units were sold worldwide and the product was discontinued in 1999 when the Power Commander II was introduced.
Power Commander II
The Power Commander II was introduced in 1999 and featured the latest surface mount electronics. Additional features were added like the faceplate button adjustment. The Power Commander II also allowed fuel and ignition adjustment on select models. The PCII utilizes "sensor offset" technology to adjust the fuel curve. Signals from the various sensors on the bike are monitored by the PCII and these signals are recalculated and sent to the ECU in order to achieve the required fuel curve.
Power Commander III
The Power Commander III was introduced in 2000 and is externally similar to the PCII. The PCIII utilizes "direct injector control" technology to control the fuel curve for models that do not possess the appropriate sensors to allow sufficient fuel adjustment using the PCII technology. The PCIII takes the injector pulse from the ECU and changes the pulse width signal to the injectors.This unit allows "Fuel Only" adjustment.
Power Commander IIIr
The Power Commander IIIr was introduced in November 2000 and utilizes the same "direct injector control" technology as the PCIII. The "r" version contains additional circuitry and in some cases, additional connectors, which allow Ignition adjustment as well as fuel adjustment. Ignition adjustments can provide very positive results on the race track, where factors like special fuel and highly tuned engines are used.
Power Commander III USB
The Power Commander III USB was introduced in 2003 and utilizes the same "direct injector control" technology as the PCIII. The USB (Universal Serial Bus) port provides an instant, no-hassle way to connect the Power Commander module to a computer. This model also features an expansion port for future add-on modules like an ignition module.
The Power Commander III USB with Wide Band Sensor technology
The Power Commander III with Wide Band Sensor technology was introduced in 2005 to deal with the closed loop area of the BMW motorcycles. This module includes a Bosch 5 wire wide band sensor that replaces the stock narrow band sensor. With the wide band sensor in place the Power Commander is able to monitor the air/fuel ratio and constantly adjust the fuel curve to the target ratio which can be set in the software.-taken from exoticsportbike
Currently I'm running the PCII and the availability and additional options available on the PCIII USB makes it very tempting to get one.
