Please Explain the Power Commander

[Dean129]

Please Explain the Power Commander to me. I don't know anyone with one, or else I'd ask.

 

[quasi888]

It's a module that attaches to the ECU of fuel-injected bikes. The PowerCommander is but one example; there are other similar products available (Yoshimura EMS, FactoryPro TEKA to name a few).

A stock bike's ECU (engine/electronic control unit) will have its own built in mappings for fuel delivery, optimized for the stock intake (airbox) and exhaust systems. These stock mappings usually work "well enough" -- if you keep the bike stock.

Once you introduce other variables into the intake/exhaust equation (e.g. higher-flowing air filters, full exhaust systems) the stock mappings no longer provide optimal fuel delivery to match the increased flow of air. End result is an air-fuel mixture that is too lean -- i.e., too much air coming through per unit of fuel. At best, a lean mixture will result in power loss at mid and upper RPMs. At worst, it can lead to engine failure due to overheating. (Running too "rich" -- too much fuel -- is better/safer than running too "lean".)

This is where a PowerCommander (and similar products) come in. These are programmable units that allow the fuel delivery (and in some cases, ignition timing) to be tweaked in order to optimize the air-fuel mix, and therefore, optimize the power band. On the PowerCommander at least, the fuel delivery can be minutely tweaked all across the RPM range. The programming can be done by a trained technician with the bike on a dynamometer, creating a custom map for that particular bike; or, widely available standard maps are available via download for common bike/modification combinations (e.g. "2004-2005 Suzuki GSXR600 with Yoshimura full exhaust"), which can then be uploaded to the unit via computer and USB cable.

Bikes tend to come from the factory with the stock ECU fuel delivery slightly on the lean side (for emissions and fuel economy purposes), so even a stock bike may benefit from these modules.

 

[Sidewalk]

In maybe more simple terms, it is a piggyback ECM. It uses the base information on the stock ECM, and changes the signals as needed based on programming.

 

[wannabe]

And, just in case it wasn't clear in the above posts, the 'map' is the bike's air/fuel mixture setting at various throttle settings throughout the entire RPM range of the motor.

As quasi mentioned, the stock map for almost all bikes are purposely lean in order to help the manufacturers meet the emissions regulations.

 

[ALANRIDER7]

This is a zero map for Yoshimura's EMS3 unit. The numbers allow you to change individual injector signals for both engine rpm and throttle position. You can go richer or leaner depending on what the bike is doing. It's pretty complex.

 

[Diezel]

This is a zero map for Yoshimura's EMS3 unit. The numbers allow you to change individual injector signals for both engine rpm and throttle position. You can go richer or leaner depending on what the bike is doing. It's pretty complex.

Let me clean up a bit of what alan said. ON MOST units when done, you can control INDIVIDUAL injectors, and their fuel adjustment. HOWEVER, most units do a "general" modification of the amount of fuel deliverd (Air Fuel Ratio). Meaning in General it changes ALL of the injectors the same amount.

Honestly, I've installed MANY Power Commanders, and if you are looking to modify the intake and exhaust of a fuel injection bike, a power commander or other comperable unit is a must. However (again) even on a stock bike they can make a huge difference in driveability (how well the bike runs and feels).

I would say they are one of the best mods you can do for the money.

 

[Dean129]

It sounds a lot like a VTec controller for honda/Acura cars.

So what are some experiences you've had with the power commander? My bike is plenty fast for me right now, but if it's a good upgrade to my bike that will be better for it, I might pick one up.

 

[Sane_Man]

It sounds a lot like a VTec controller for honda/Acura cars.

My MR2 has a Dastek Unichip that works the same way, but only the Dastek dealer has the software to change the map, which needs to be tuned on a dyno anyway.

 

[elskipador]

ON MOST units when done, you can control INDIVIDUAL injectors, and their fuel adjustment.

to the best of my knowledge individual injectors can NOT be changed, its all injectors or nothing.

 

[Diezel]

to the best of my knowledge individual injectors can NOT be changed, its all injectors or nothing.

On some higher end models in the piggyback world you can change individual injectors. And if the P/C's software allowed you to do it, since it has individual channels for each injector you could do it too.

 

[elskipador]

i've worked with all the power commander models, the yoshi box, the teka and the EMS and i've never even seen a spot to click to change just 1 injector. the yoshi box does have a spot where you can set each individual injector's idle fuel, but if you use it you have to sync the throttle bodies after. i'm only talking about bikes not cars.

 

[Diezel]

i've worked with all the power commander models, the yoshi box, the teka and the EMS and i've never even seen a spot to click to change just 1 injector. the yoshi box does have a spot where you can set each individual injector's idle fuel, but if you use it you have to sync the throttle bodies after. i'm only talking about bikes not cars.

Atleast the yosh allows it. And i was speaking in general with the piggy back units. I only wish some of the lower end units allowed for cylinder tuning.

 

[elskipador]

why would you want that? i guess its sorta like the staggered jetting thing?

 

[Diezel]

why would you want that? i guess its sorta like the staggered jetting thing?

Every single cylinder is going to have it's own tune to it. Based off of simple items such as compression, ignition point and effiency, intake runner deficiencies, etc...

Having the ability to tune each cylinder to it's absolute peak, and still keep it within reference of the other cylinders will give you an engine runing at it's 100% peak and very reliable since all the short comings of each cylinder will disappear.

 

[elskipador]

i can understand how that'd be great on a car or other such engine with a single throttle body, but with multiple bodies i don't think you'd need the option. since most fi bikes sync with the air/fuel mixture screw, your gsxr1300 being 1 of them, if you did change an individual injector it'd throw the sync off, and if you sync'ed to compensate it'd throw the injector adjustments off.

 

[RedNosePit]

The throttle response on my 01' 929 was jerky, after talking to Honda they said it was a common complaint on the 929. I bought a PCIII and now my bike is smooth when I am ion the throttle and the bike is much smoother when I let off the throttle.

As a side note- I thought CA bikes ran a tad leaner from the factory then 49 state bikes? (do they even have 49 state bike and a CA edition anymore) My bike was purchased out of state so any settings I may have might not work for a CA bike....or am I just talking out of my ass???

 

[elskipador]

As a side note- I thought CA bikes ran a tad leaner from the factory then 49 state bikes? (do they even have 49 state bike and a CA edition anymore)

yes and yes. however i think they're going to 50 state models in 07 or 08.

 

[klepto]

The throttle response on my 01' 929 was jerky, after talking to Honda they said it was a common complaint on the 929. I bought a PCIII and now my bike is smooth when I am ion the throttle and the bike is much smoother when I let off the throttle.

As a side note- I thought CA bikes ran a tad leaner from the factory then 49 state bikes? (do they even have 49 state bike and a CA edition anymore) My bike was purchased out of state so any settings I may have might not work for a CA bike....or am I just talking out of my ass???

My 954 has the same problem. Just starting to crack back the throttle the bike seems real jerky. Its great to hear that the pcIII helps this, im gonna give it a try.