ECU Reflash vs. ?

[phif]

If someone could kindly explain what the difference is between reflashing the ECU and having a EJK or tuning the bike that would be excellent. I think my main point of confusion is if they all do the same thing. I just bought the carbon akrapovic exhaust and plan on doing something to get more power out of the bike after I install it. I also have a friend that has a shop with a bike dyno in it which I would have access too. Thanks.

[xdr]

Flashing is taking the ECU and having the stock tune file overwritten with the custom one. The modules like EJK don't due that, they have their own chipset and plug in to the harness in between components to alter/trick the stock tune. I think that is the most basic way to explain the differences.

[bmwpowere36m3]

EJK or a piggyback system can only alter fuel delivery or amount. The stock ECU calculates the "required" fuel, a signal is sent to the injectors, the piggyback system reads that signal and then alters it and send it to the injectors instead. Fuel changes can be made on-the-fly and to your hearts content.
 
ECU flash can alter almost any parameter that the stock ECU can control, like: fuel, timing, idle RPM, coolant fan ON temp, rev limit, etc… The parameters are loaded into the ECU and that's it… looks and works like a "stock" system. Any changes require the ECU to be flashed again…. usually means shipping it off.

[2wheeldynoworks]

We do a lot of fuel tuning, it's still a great way to get a decent tune out of a bike. But with it there are limitations that can't be tuned out. Flashing the ECU is how you overcome those limitations, and control everything in the bike. Fuel is not even half of what a full tune takes. The flash, is the full meal deal and we get to make every last option as efficient as possible

[snowdriftless]

Fuel Controllers/Piggyback systems modify the fuel signal to add or remove fuel based on certain parameters (throttle position and engine RPM primarily).
 
Dynojet uses throttle position and RPM and has a grid that you can specify where to add and subtract fuel (like an Excel spreadsheet).
 
EJK simplifies the adjustment and gives you 3 ranges where you can add and subtract fuel (Cruse, Acceleration, and Full Throttle). This makes the process of tuning easy because you only need to worry about 3 or so values as opposed to every different combination of throttle position and engine RPM I believe that EJK also takes into account how quickly the throttle is opened.
 
(Aside: EJK stands for Electronic Jet Kit, the three ranges roughly correspond to the three jets you would find in most carburetors; idle, pilot, and main).
 
An ECU re-flash is changing the fuel settings in the bikes ECU itself so you are cutting out the "Middle man" of the piggyback system, you also have access to all the parameters that the ECU may use or have control over (e.g. when the cooling fan kicks on and off in the example above).
 
Piggy back systems are easier to modify fueling, you don't need to send your ECU to be reprogrammed. Piggyback systems lag in the fact they cannot add fuel where the stock map doesn't have any fuel. I know that the FZ-09 cuts off all fuel when the throttle is closed and the engine is over 4000 RPM, I would imagind a similar thing is occurring on the FZ-07. This is a contributing factor to jerky on/off throttle response and hard engine braking that a piggyback system may not be able to resolve.
 
An optimal (and Pricey) solution would be to get your ECU re-flashed to the best stock map available and then add on a piggyback system to compensate for any modifications you make. But this might require a dyno session as most people only use one or the other.
 
I hope that helps.