Fuel

[MickB]

New to the world of BMWs and have been dutifully reading the handbook for my 1200s. I was a little surprised to see that that the fuel of choice was 98 or super unleaded. Just wondering what people are using and can anyone notice the difference between the 98 and 95 octane fuels?

[milleplod]

I mainly used 95 in my 1200ST for the 6/7 years I owned it - it ran fine, I never noticed any loss of performance tbh. Every now and then, I gave it a tankful of 98 - I do think it ticked over a little smoother, and pickup was perhaps a bit better at lower, round-town speeds. Some people say that mpg is better on 98, bit academic really when it costs more! Personally, I wouldn't fret about it - doesn't it say somewhere in the handbook that its OK to use 95, I can't remember tbh!

Pete

[Justcruising]

Fuel Octane requirements is predominantly dictated by the engine compression ratio to assist in controlling the rate of fuel combustion to optimise performance while avoiding pre-ignition (damaging). The R12S has quite a high CR at 12.5:1, for a petrol engine and hence the recommended RON98 Premium Unleaded Fuel specified. Fortunately the engine management system is smart enough to adjust (retard) the ignition timing for lower octane fuels to avoid pre-ignition. The resulting change in performance is probably not easily detectable with most casual riding. Personally i don’t see the point in owning a high performance engine in anything, then running a substandard fuel ... but everyone to their own. I’d also avoid any ethanol blends if possible.

[Humbug]

I use 98 when available as I am of the same mind as Justcruising. Don't think BMW have shares in all of the fuel companies so no benefit in specifying 98 unless its needed. I use 95 as well and difficult to tell the difference on the road but i'd rather not use the knock sensors to retard the timing when i can use 98 and have them sit quietly in the background doing nothing.

[kfrogzx7]

I use 98 when available as I am of the same mind as Justcruising. Don't think BMW have shares in all of the fuel companies so no benefit in specifying 98 unless its needed. I use 95 as well and difficult to tell the difference on the road but i'd rather not use the knock sensors to retard the timing when i can use 98 and have them sit quietly in the background doing nothing.

+1

[MickB]

Wise words indeed. 98 it is. First ride tomorrow!!

[GerryB]

Here in Spain , mostly 95 , and 95 super ....

So , I use the 95 super, much dearer , but I'm assured there is no rubbish in it .

My bike runs pretty good , so I'm not complaining .

[BoxerCup R]

Highest Octane I can get every time for my car and bikes, irrespective of price I want the engines to have the best available

[Tommy T]

Off to Italy on the 11S just wondering about what fuel to use?
Should I avoid using E10.
The bike is a 2000 model with 7000 miles on the clock.

[Boxered]

Off to Italy on the 11S just wondering about what fuel to use?
Should I avoid using E10.
The bike is a 2000 model with 7000 miles on the clock.

?

So its an 11S then? if so just put in whatever is cheapest,
I have to say that my R12S runs much nicer, smoother and happier on premium 97/98/99
and fuel consumption is much better too, I often have to use 95 'cos it's difficult to get
premium in most parts of Wales and Yorks ( locals too tight to pay the price I reckon )
On 95 it can run ok, but usually only if its a decent brand like BP/Shell? Esso/ Texaco.
If its Murco or some other dodgy outfit it generally runs rougher, down on power and the consumption drops
considerably.
All in my 'umble opinion of course YMMV

Seve

[Justcruising]

Off to Italy on the 11S just wondering about what fuel to use?
Should I avoid using E10.
The bike is a 2000 model with 7000 miles on the clock.

Check your Rider's Manual for the correct fuel specification. I believe the R11S has a compression Ratio of 11.3:1 which should require 95RON premium unleaded for optimum performance and longevity. WRT ethanol blended fuels, I would recommend avoiding them at all cost in our bikes … this article might help convince you. https://www.cycleworld.com/real-world-look-at-alcohol-in-your-tank .

Safe trip & good luck!

[Crazy Kev]

I used 4* for 4yrs - now using 5* 0ver the last few months and have noticed a better response!

[boxerscott]

Off to Italy on the 11S just wondering about what fuel to use?
Should I avoid using E10.
The bike is a 2000 model with 7000 miles on the clock.

All petrol has ethanol in it I do not think E0 exists at our filling stations, E10 is the higher percentile ethanol additive. E5 is more available in uk and that is what Barry Sheene used so it must be good! E10 is more common in Europe you may have no choice, Higher octane fuel still contains the ethanol percentile. Not sure I have noticed any difference putting in Higher spec fuel than lower spec. What is not good is leaving the bike standing for long periods of time. The Ethanol element separates and then gets up to mischief with fuel pump assemblies, plastics and ferrous stuff. If you don't use it you lose it! This is one situation where the higher alcohol percentage is not good. lets face it when the fuel lamp is on and mile counter is low you have little choice.

[MR SHEEN]

Unless you are on the Autopista you will not get 98/99 good fuel period and forget paying cash most fuel stations are unmanned and automatic so carry more than one credit card some of ours didn’t work.