AIR FUEL RATIO CONTROLLERS (Power Commander, Bazzaz etc) versus ECU REMAPPING

This is the one question that arises in a buyers mind often when it comes to street and track bike tuning. So we will give you our perspective. We will start by saying they’re both excellent at what they do. And maybe the best way to go about answering this in a way everyone can understand is to describe what they both can do and can’t do.



They intercept and change the signal from the Engine Control Unit (ECU) to the injectors, adding or taking away fuel during combustion. This alters the Air Fuel Ratio (AFR) of the bike, more fuel equates to a richer AFR, less fuel a leaner AFR. And if not tuned properly then,

 Rich AFR’s Will Present These Issues:

  • Dirty exhaust pipe or soot and excessive smoke (unburnt fuel)
  • Cooler combustion and exhaust temperatures
  • More emissions to the atmosphere
  • Less power

Leaner AFR’s Will Present These Issues:

  • Too lean – high combustion and exhaust temperatures, engine damage – holed pistons etc
  • Detonation




 The ECU’s internal settings or parameters are edited so that the AFR’s are changed to bring them closer to the ideal 14.7:1. And usually aimed for anywhere between 12.8 - 13.1 at Wide Open Throttle (WOT) as this provides a safety margin. ECU remapping can achieve this without hacking into the bikes wiring or having additional components strewn throughout the bike by altering the existing factory maps.


Timing tables or maps can also be edited. Altering (advancing) the bikes timing is where more power can be safely gained over border line AFR’s. Fuel controllers cannot alter a bikes timing. Factories sometimes install timing retards in the first three gears of their bikes to lessen the power hit. People sometimes fit Timing Retard Eliminators (TRE’s) to combat this, again more wiring, modifications and components to install. When an ECU is remapped, these retards are simply removed and you’re good to go without the need of a TRE.


There are many settings and limits which can be changed or removed when an ECU is remapped. Some of which are listed below:


  • Top speed limiters can be removed
  • Idle speed can be increased/decreased  (Race applications)
  • Rev limits can be increased, this sometimes lets you pull a gear that bit longer before having to shift or have the rev limiter savagely cut in adding to your lap times.
  • Thermo fan cut in temps can be altered
  • Deceleration maps can be altered giving a much improved throttle transition and removing that dreaded snatch.
  • Optimized Fuel & Ignition Maps
  • Eliminate Factory Throttle Restrictions
  • Optimized Throttle Maps
  • Eliminate Timing Retard
  • Injector Phasing Adjustment
  • Remove Factory Top Speed Limiter(Gear dependent)
  • Eliminate Factory Fuel Cut / Optimize Off-Throttle (Deceleration) Mapping
  • Remove Injector Shut-Off on Deceleration
  • Optimize Variable Velocity Stack Timing
  • Disable Closed Loop Routine (For Use w/ Auto Tuning Air/Fuel Modules)
  • Disable Factory ?Error Code(s)?: Exhaust Servo Motor/Valve, Pair Valve System (Smog   Valve), O2 Sensor/Lambda, Steering Damper and more
  • Cooling Fan Temperature Adjustment (For Race Applications)
  • Disable Factory Immobilizer (For Race Applications)
  • Increase Acceleration & Top Speed
  • Improve Throttle Response & Control & Reaction
  • Velocity Stack Switching Adjustment (Variable Stacks Only)
  • Race Fuel Mapping Accommodations
  • Power Mode Adjustment

Proponents of Power Commanders are usually tuners or customers who will fit your fuel controller then give a “custom tune” for your bike and its modifications. They do this by adjusting the fuel controller until they are satisfied with the AFR’s throughout the rev range of your bike, you then give you a print out that shows the AFR curve as well as power and torque curves. The issue here is that it is very easy to manipulate the results of the dyno graph to show a much larger gain than you actually got. This is a problem throughout all disciplines of automotive tuning.

These so called tuners will argue that manufacturing tolerance deviations will produce bikes that are all profoundly different and require custom AFR tuning. Our take is that modern manufacturing processes now punch out bikes that are so closely cloned that I’m not sure this is such an issue any more, let’s face it, all the bikes feel pretty much the same off the show room floor.

Our ECU tuning includes developing the tune both on the track and on the dyno in every conceivable state of modification and develop tunes for each of these, for example there will be an optimized tune to suit an R1 in stock trim, then another tune developed for the bike with a slip on, then another with a full system and so on. So the end user will get a tune pretty much customized for their bike if they tell exactly what they have done. And there is always a factor of safety built into these tune files to ensure reliability.



Benefits of Remap:

  • Handling more predictable
  • Have more control over your ride
  • Heat issue reduced
  • Better corner entry and exits
  • Reduced jerks while accelerating during a gear change
  • Smooth ride is required on track more than peak horse power
  • Smoother acceleration and power delivery
  • In cases engine heating is reduced to a great extent
  • Engines can be tuned for lower or higher octane fuel


We develop our state-of-the-art Remaps not only for maximum power increase but we also significantly smooth out the power/torque curves making the bike more consistent feeling. This helps a ton with the jerky on/off throttle that is notorious in most modern sports bikes. It helps eliminate upsetting the chassis during mid corner throttle corrections, while also assisting in corner entry and exit. We also work on the deceleration maps which considerably help corner entry. It reduces the amount of engine braking that comes on when decelerating for a corner.

 On most of today’s modern fuel injected sport bikes, the factory shuts the fuel injectors off immediately when the rider lets off of the throttle. They do this, to lower emissions on the vehicle and justify this by saying, fuel is only needed to accelerate. However when the fuel injectors are shut off and stop delivering fuel in such an abrupt method the results are normally not very good on ride-ability.

2 of the main problems that result from this are (1) The bike will have a very choppy on/off throttle control which not only makes for a “jerky” feeling under normal riding conditions but will also significantly upset the chassis during corner entry, corner corrections, and corner exits. What we at UD MOTOR X take the time to improve and adjust these deceleration maps that slowly and consistently ramp the fuel down as you let of the throttle making for a smooth and predictable deceleration and/or on/off throttle control. The deceleration can improve track times as much if not more than a quality fuel map. High speed corner entry becomes very smooth and less violent helping the suspension geometry work for the rider instead of against, mid corner throttle corrections are now very linear with reduced ON/OFF throttle jerk, and corner exit is consistent because the fuel is down being increased and decreased in a very linear and cohesive manner.



For some selected bikes we offer REMAP+SPROCKET Kit with our designed and developed sprockets designed to be light and super strong which massively increases your torque without compromising on top speed.