Issues with Factory Fuel Injection Map
(created: 12Jul11 updated: 28Jul22 - Michael Holzer; 2Aug22 - Engenia)

The fuelling on the 900 & 1130 is good at high revs, but less than perfect at mid to low revs, where it spends most of it's time in everyday use. Perhaps this is due to:
  1. Benelli's choice of injectors,
  2. noise or emissions requirements,
  3. the ability of the ECU,
  4. it's track oriented heritage,
  5. to compensate for the very limited motor cooling in stop & go city traffic
  6. they just got it wrong.

This has been discussed on the Benelli forum in the past, and no doubt will surface again.

Improve Fuel Consumption
I installed a wideband oxygen (lambda) sensor to the exhaust, and took some air/fuel ratio (AFR) data, using an Innovate LM-1, under various conditions, and discovered that my 900 was running very rich at low revs, which I thought at the time was causing the plugs to foul - it wasn't, but more on that elsewhere. At around 6,000 rpm, & fast cruising, the fuelling was just about at stoichiometric. No surprise that that was where it delivered it's best economy.
The challenge was to improve the fuel map, improving the reliability of the bike & it's endurance. I was sick of being the one who forced a fuel stop on everyone. (The 1098 is now the but of all the jokes!)

How do you improve the map ?

  1. The traditional way, is to hire some dyno time, and measure the power characteristics of the engine.
    1. Do a dyno power run
    2. Make an educated guess as to the changes required in the fuel map, in order to arrive at the ideal power characteristic & desired AFR.
    3. Upload the newly modified map to the ECU, or fuel controller
    4. Repeat A B & C until the AFR error is acceptable

  2. The long winded, but far cheaper and more "real world" method of determining the new map, is to record data under repeatable conditions.
    1. Go for a ride & record the throttle position, rpm and AFR under known conditions - terrain, temperature, aggression etc.
    2. Analyze the data in much the same way as would be done when using a dyno. An educated guess is made for each fuel map cell, in an attempt to move the AFR to the desired value (~13:1 for power, 15:1 or higher, for economy).
    3. Upload the newly modified map to the ECU, or fuel controller
    4. Repeat A B & C until the AFR error is acceptable
    The required data is recorded with the help of a data recorder. Data recording is a feature of TuneBoy or other tools, such as an Innovate LM-2

  3. Then there is the automated method. A closed loop controller measures the AFR for each cell in the map, as it encounters it. It then makes an adjustment and builds it's own map. At the end of the ride, you choose whether to store the new map permanently, or discard it. This requires a Motty AFR Tuner (AT) or Power Commander 5 with Autotune (PCVA).
    The beauty of this automated method, is that the map is adjusted constantly, as changes occur in altitude, air flow (filter clogging), exhaust back pressure (changed or failing can) or even fuel pressure.
The last method covers all the bases, and is the system I installed. It resulted in a dramatic improvement in fuel economy, from around 220 km from a tank, to over 300.
As a bonus, the AT provides an extra map. I use the first when I'm looking for economy on transport sections. The other, the "go faster" map, can be switched in when the road gets "squirrely", providing power immediately from 4000 rpm, to the limiter.

How do you apply a changed fuel map to your motorcycle?
A couple of possibilities:

  1. Download a new map to the ECU, using a tool that talks to it, via the diagnostic connector. That tool could be the Axone 2000, or a laptop running Tuneboy, or similar application. These tools can also read & reset any error flags that the ECU has logged.

    Axone 2000
    		 Axone is the standard tool used by Benelli and several other manufacturers. It's ~$2000 & not that easy to come by. It can talk to many different ECU's though, if you have the right interface cable & installed software.
    TuneBoy Default Screen Tuneboy Sensors Window
    		 Tuneboy works similarly to Axone. It runs as an application on a PC, and talks to the ECU with a special RS232 or USB cable, but it is locked to a single ECU serial number. Certain variants are a bit smarter than the Axone though, as they can also take engine data, such as throttle position & rpm, and external data from a wideband O2 sensor, which, with the correct equation, will provide the air/fuel ratio (AFR). With this setup, you can modify your own injector timing (fuel) map.
    TuneECU Start Screen TuneECU Mapping Screen
    		 TuneECU works similarly to Tuneboy but is much cheaper. It runs as an application on an Android SmartPhone or Tablet and talks to the ECU with a BlueTooth OBD adapter or special USB cable. Note: The freeware Windows version is no longer supported but still works!
  2. Or, you can bypass the map in the ECU, and add a fuel controller between the ECU injector outputs and the injectors themselves. This controller is given it's own fuel map. The ECU triggers the injector pulse, but the controller inserts it's own pulse width. Established products are Power Commander or Motty Electronics AFR Tuner (no longer available as new product)

    AFR Tuner
    		 The Motty AFR Tuner (AT) is a closed loop controller. Initially, it uses the OEM ECU injector map, but it is also given a target AFR map, downloaded from a PC. It reads the current throttle position, rpm & AFR (from a wideband Oxygen sensor), and compares the actual AFR with the target AFR. It then builds & adjusts it's own fuel map to reduce the AFR error.
    Power Commander V + Autotune
    		 The Power Commander V + Autotune,
    The V is an open loop controller when used alone. Give it an injector timing map, and it will use that to control the injector times, dependant on throttle position & rpm. Combined with its AutoTune addon it works in a similar manner to the AT, by building it's own fuel map from the target and actual AFR values.