Sportbike Forums on WristTwisters banner
1 - 5 of 5 Posts

·
Registered
Joined
·
22 Posts
Discussion Starter · #1 ·
I saw there is a Procom PE-PJ-007 Powerjet Fuel Controller availiable for the CB919. It looks like a dumbed down version of a power commander. It is about $120. It looks like it just fools the bike into thinking the air temperature is hotter or cooler to make the bike richer or leaner. Anyone try this?

George
 

·
McTavish
Joined
·
6,545 Posts
I saw there is a Procom PE-PJ-007 Powerjet Fuel Controller availiable for the CB919. It looks like a dumbed down version of a power commander. It is about $120. It looks like it just fools the bike into thinking the air temperature is hotter or cooler to make the bike richer or leaner. Anyone try this?

George
If that's all it is, i.e. an Intake Air Temp spooking device, it's a waste of money.
The reality is this, the factory mapping for the 919 is not simply "lean" or "rich". Instead, it's "lean here and rich there" across the Throttle Position X RPM matrix that makes up the Speed-Throttle Map. The device you are looking at can only do one thing, and without any variance during varying engine conditions.

Here's a wee bit on the two kinds of maps the 919 has:
The ECU contains two maps, one is a Speed-Density Map, the other is a Speed-Throttle Map.
The ECU selects which one to use.
(Which also means there is a transition zone between the two, and that zone will surely vary as a function of a number of parameters inputted to the ECU to enable the change map decision.)
Both Maps determine a required volume to be injected, said volume controlled by the ECU issued pulse width signal to each injector, all being highly reliant upon a stable and standardized fuel rail pressure level in order for the determined volume delivery requirement to even be possible on a repeatable basis.

The Speed-Density Map is used for Low Loads X Low TP % Openings, and is dominated by the MAP and RPM (my understanding is that high RPMs under no load are controlled by S-D M’).

The Speed-Throttle Map is used for Higher Loads and Larger Low TP % Openings, and is dominated by the % TP Opening and RPM.

Because the PC is a piggyback device only, it does not hold complete maps, so only map changes to be layered upon the two maps in the ECU, are actually held by the PC.
 

·
McTavish
Joined
·
6,545 Posts
See this as added insight re the "Lean Here and Rich There"
The red shading indicates Leaning required.
The green shading indicates Enrichening required.
Then look at the values of how much Leaning or Enrichining is required.
True, the mapping correction is for good slips ons, but the same concept holds for a bone stock 919.
 

Attachments

·
Registered
Joined
·
22 Posts
Discussion Starter · #4 ·
I was hoping to find a review from an actual user. Based on what you said, fuel mapping is a much more complex process. It just tweaks air temperature. However, it might improve issues with aftermarket slip ons. Possibly reduce some of the idle stink. Still a mystery.
 

·
McTavish
Joined
·
6,545 Posts
I was hoping to find a review from an actual user. Based on what you said, fuel mapping is a much more complex process. It just tweaks air temperature. However, it might improve issues with aftermarket slip ons. Possibly reduce some of the idle stink. Still a mystery.
Unfortunately, I don't remember ever seeing a review here, but the topic has come up before as there's a number of suppliers of such devices.

Here's another way to look at the air temp spooking box.
Let's imagine it is set up to fool the ECU into thinking the air is a bit colder, therefore more dense.
So the bike will run even richer in the rich zones, and less lean in the lean zones - while still being lean is my guess.
Then imagine again the set up is to fool the ECU into thinking the air is a bit hotter, and therefore less dense.
With this scenario, the bike will run leaner in the rich zones, but be even more lean in the lean zones.
 
1 - 5 of 5 Posts
Top