GSA tuning advice

[elefantman]

Does anyone know at what point the knock sensor kicks in ,im guessing you don't have to alter the a/f ratio much to get this to start retarding the ignition timing
Also does anyone know the factory parameters for a/f ratio ?

 

[Pukmeister]

Does anyone know at what point the knock sensor kicks in ,im guessing you don't have to alter the a/f ratio much to get this to start retarding the ignition timing
Also does anyone know the factory parameters for a/f ratio ?

Knock should have little to do with it if the air/fuel ratio is made richer. The bikes run very lean as standard.

No idea about the factory settings but a small addition of fuel will give a big improvement in driveability versus a tiny reduction in MPG (especially part-throttle), hence why the Booster Plug etc are so popular.

 

[elefantman]

I'm trying to find the point at which the k/s retards the ignition with relation to removing cat,little point doing if any gains are lost by lean running with the knock on effect of retarded ignition
Does the temp sensor not coflict with the lambda or has that now been fixed

 

[Schtum]

What you're looking for isn't really relevant. If you're going to decat the bike, get it on a dyno, have the air/fuel ratios logged and be prepared to fit a Power Commander or similar device and have a custom map made.

The lambda sensors only influence the fuelling while the system is operating in closed-loop mode, ie at relatively low revs and small throttle openings. Once the system switches into open-loop mode the fuelling is determined by the map in the ECU + applied trims which is where quick 'n' dirty mods like Booster Plugs do their stuff. However, if the engine's fuelling requirements go outside the parameters of the ECU map + trims then it's going to run too lean. Note that late model 1200s already run significantly leaner than the original '04 bikes; hence why Remus' and Akrapovic's claims that you could fit their headers without adjusting the fuelling no longer hold good.

I'd be more concerned about decatting the bike and holing a piston or similar because it the runs much too lean than I would about losing performance because the knock sensors are retarding the spark. However, I agree that if you're decatting the bike to let it breathe more easily and thus extract more performance from it, it doesn't make sense to compromise this which brings us back to the need to map the fuelling on the dyno or fit a Power Commander V + Auto Tune (wide-band lambda sensor) which, after initial setup on the dyno, will effectively map the engine's fuelling requirements on-the-fly.