99 RON vs 95 RON fuel

[Flyingscotsman]

In my opinion,as the engine has knock sensors,the ecu will compensate for fuel ron rating.I have always had my bikes mapped using 99ron and suffered no ill effects when having to use a lesser fuel.However,I will always try to use 99ron.

Cheers Baz. Good point about the ECU & part of reason for my original question. Of course back in the day before ECUs, if vehicle tuning/timing adjusted for particular RON then one should stick with that always. However now that ECUs have knock sensors & can adjust timing on the fly then it should be less of an issue.

Given that 99 (or higher) RON is less prone to knocking than 95 then even if std map is for 95 then with 99 engine should run with less input from knock sensor (timing adjustments).

Of course whether or not you get real world improvements in bhp or mpg without mapping is another question........

 

[baz]

Basically,the engine/ecu is optimised for 99rom fuel(no doubt with some leeway,which means some gains could possibly be made by playing with ignition timing) but will always tolerate a lesser fuel,purely because of the knock sensors.I stand corrected but,i think bmw were one of the first to incorporate knock sensors.
Even today,engine dyno cells use a type of knock sensor(bake bean tin or similar!)on older engines to maximise power output/ignition advance for a given fuel.The only downer with an engine set-up by this method would mean it would be essential to run the same fuel at all times to avoid detonation.

This is,of course,where in-built sensors and ecu overcome the problem.

 

[Huge]

Afternoon gents.
Anyone know where I can get 99RON down on the south coast? Only got 95 and 97, FFS

 

[Flyingscotsman]

Shell V-Power or Tesco Momentum are 99 RON

 

[Huge]

Shell V-Power or Tesco Momentum are 99 RON

Thanks pal. H