Know your ECUS

» ECU: stands for Electronic Control Unit. It’s the bike’s brain and controls everything electronic – fuelling, ignition timing, traction control, the lot. » Map: a grid of figures loaded into the ECU which it uses to do stuff. So if you’re at 10 percent throttle and 3000rpm, it looks in a table for those two conditions and the answer tells it how much fuel to squirt in.

» Look-up table: another name for a map

» ECU flash: when you load up a new map into the ECU

» ECU re-map: another name for a flash

» O2 sensor: pokes into the exhaust gases and tells the ECU whether the engine is running lean or rich. The ECU will then adjust the fuelling to hit its emission targets. » Power Commander: box of tricks used to adjust fuelling on fuel injected bikes in the days before ECUS became far more complex. Not used as much now.