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sportrider said:
Has anyone tried an octane booster in the U.S.?

Wondering what the results were?
Howdy John,

Maybe someone has given it a try, but I would take claims of "positive" results with a large dose of skepticism.

Octane ratings describe the component in the fuel that serve to increase the ignition temperatures of the fuel and to make it resistent to premature detonation. Unless the engine is "pre-igniting", or "pinging" then no increase in performance should be seen. In fact, the opposite is likely to occur. The fuel would demand more energy to ignite and burn slower than can be properly utilized by the engine configuration.

If the engine has been modified, more than simply increasing the flow through the air filters, by increasing the compression ratio of the engine or, and, increasing the volume of air in the fuel/air ratio via some sort of compressor (turbo/super-charger), then an increase in fuel "Octane" would serve to lower performance.

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I understood the engine management systematically advances the ignition timing until the knock sensors in the engine detect pre-ignition then it backs it off a little. The engine is obviously capable of running on a range of octane rated fuels.

At 13:1 compression I believe there probably is scope for higher octane fuels to be used with a positive effect but logic suggests the engineered upper useful limit is likely to be the highest that is commonly available. Engine builders don't build high compression engines because they like the work - they do it because there are performance benefits particularly in torque output. But higher compression means greater engine stress and closer attention needed to ignition timing plus fuel octane to avoid pre-ignition.

Just watch out on the avgas as I believe it is highly leaded and maybe octane boosters for lead based additives and exhaust issues if you're running a catalytic converter. Leaded fuel or similiar additives are not good for cats (or dogs, canaries, humans..........................................)
 

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BillyOmaha said:
...Unless the engine is "pre-igniting", or "pinging" then no increase in performance should be seen...
This is the standard viewpoint, but modern engines with knock detectors can change things. It varies from engine to engine based on ECU programming and knock detector sensitivity, but higher octane can result in significant performance increases. This is because the ECU advances ignition timing until it hears knock then backs off. Higher octane fuel allows more ignition timing advance hence more horsepower and performance.

A good example is the BMW M3, which has separate knock detector microphones for each cylinder. In this Car and Driver test, it got measurably better performance on premium fuel: http://www.caranddriver.com/features/3604/regular-or-premium.html

The K1200S has two knock detectors for its four cylinders. I don't know what the hp difference is for regular to premium or if there's any further advantage in an octane booster. In theory there might be, but I'd like to see dyno results.
 

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Thanks joema,

An excellent article.

I suppose that an if the engine was designed such that greater performance may be obtained by advancing the ignition timing greater than would be supported by normally available fuel, then maybe a bit of a power increase could be found.

Unfortunately, the Car and Driver article didn't go that far with the testing.

My expectation would be that even the mighty BMW K motor is designed for maximum results using nominal "premium" grade fuels and that the extra Octane would result in, at best, a minor increase in power, say 0 - 3%.

But,that's just my SWAG. A side by side test would be most interesting.

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Dunno about octane booster but I fill with Shell V-Power (99 octane) and my bike is now smoother (not perfect but better).
 

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hass said:
Dunno about octane booster but I fill with Shell V-Power (99 octane) and my bike is now smoother (not perfect but better).
At 13:1 compression this engine ain't kiddin. As I've suggested before I've seen speedway bikes (single cyl 500cc 4strokes) run methanol from about 13.3:1 quite happily. Subtle shifts in ignition timing change the output bias (low end torque or top end). With the ECU optimising the timing to match fuel etc this thing would probably run on fuel from pen ink to alcohol - with output to match. (well maybe not pen ink but you know what I mean)
 

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Discussion Starter #8
That's why I brought it up, because in Europe they can get 98+ Octane, over here the max is 93, so in theory, it should have no problem boosting the octane to 98.
 

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sportrider said:
That's why I brought it up, because in Europe they can get 98+ Octane, over here the max is 93, so in theory, it should have no problem boosting the octane to 98.
Europr rates the octane number with the RON.
USA rates with the average of the RON and the MON, also known as the Pump number
98 RON in Eurpe is equivalent to 93 (R+M)/2 in USA.
 

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i use the NOS octane booster ( the racing formula ) with premium 92.
it's availlable at wall mart and other car places

i use half a can for a tank of gas,and you can feel the difference in the seat

well i used to, until my S has stopped pulling hard.
now it doesn't get agressive anymore above 7000
stroker
 
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