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But r00t is in Atlanta. The manual for the RS says, "These Triumph motorcycles are designed to run on unleaded gasoline with a CLC or AKI octane rating (R+M)/2 of 87 or higher." -Page 94 r00t, are you reading from a non-US manual? If you're in Atlanta and you can get ethanol free 87, I'd definitely go that route.
You guys are right - I was looking at the .pdf that I downloaded from the UK site (same that Yodie_765RS quoted above).

Then I checked the paper one which came with the bike and it has exactly what beatle quoted.

So I can safely run on ethanol-free at either 87(QT) or 90(Shell).

Thank you for clarifying!
 

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This is exactly my understanding, and I'm losing my mind trying to find out if the 2017 1200s have any sort of knock sensor. It's certainly a shame if they don't seeing how much electronics the bike has. Hell, Buick was using knock sensors in the mid 80s!
What are you talking about? How would having a knock sensor result in any change when running higher octane?

The controlling factor for octane needs is the compression ratio of the motor. The higher the compression the more likely either preignition (fatal) or detonation (annoying/damaging) will occur. Higher octane fuels avoid this.

A knock sensor senses....wait for it....spark knock a/k/a detonation. A knock sensor can help an engine decide to retard timing to avoid this unwelcome detonation which is often a result of running *too low* of octane fuel for a given motor or from running settings, such as advanced ignition, that result in detonation due to not utilizing the optimal timing. A knock sensor is not really used to dynamically advance timing. More importantly, advancing timing does not magically increase power.

This is because optimal ignition timing is a function of engine geometry taking into account the air/fuel ratio and engine speed. There is always a mathematically ideal point for ignition which will result in the strongest force on the power stroke. The goal is to get as close to that ignition point as possible, dynamically adjusting for engine speed and air/fuel mixture. Modern ECUs handle this beautifully.

If the motor is designed to use higher octane fuel it will utilize the knock sensor to dynamically retard timing to make sure no detonation occurs if lower octane fuel is used, but simply running higher octane fuel in a motor designed for lower octane which has a knock sensor will do nothing. Absolutely nothing. Except waste your cash.

The only way a higher octane fuel will produce a benefit is if it is needed. The only reason it'd be needed is A) your running a higher compression ratio than stock (did you rebuild your motor?) or B) you are running advance timing && getting knock.

The only reason to run advanced timing is because your air/fuel ratio changed and the optimal ignition point changed as a result. The only reason to change your air fuel ratio is A) if you believe the factory did not set the ideal ratio OR B) you change hard parts (such as exhaust) affecting the ratio.

(A) is probably true. Because of emissions laws and reliability concerns, most modern vehicles (cars and bikes) have a tendency to run on conservative air/fuel/timing settings. This is why you can flash an ECU, especially on a modern turbo, and see legit power gains on a dyno even without any mechanical changes to the motor. This is because the car came from the factory with settings designed for reliability/fuel efficiency/emissions and not straight power. The trade off is that the motor is absolutely under more stress. It's sort of like overclocking a computer CPU. You know the manufacturer under-rates for some quality control purposes, so maybe you risk it. And these changes are to air/fuel AND timing, not just timing.

Also, if you make changes which effect the mixture (exhaust/larger intake/turbo/etc), you may *need* to make those changes in the ECU in order to run safely.

However, for a stock motor on a stock ECU with stock air/fuel mapping, the only way advancing timing alone would ever do ANYTHING is if you think the Triumph designers got it wrong. Do you think they got it wrong?


Running pure gas will result in performance increases not because of octane ratings but because pure gas has more power density than E10. If you can get it, run it. You will see higher MPG in cars too, which may help cover the difference in price.
 
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