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I'm planning an extended trip to northern canada next month and from what I can tell, low test is the only option at most of the fill stations in the areas I'll be heading. So my question is: is there anyone on the board who has been running 87 in their MTS1200 for extended periods of time?

I did a search but it seems most of the threads that cover this topic just end up turning into a lesson on how to calculate octane or people debating the benefits, etc... As interesting as all of that is, really what I'm just looking for is if anyone has done 5,000km+ on low test?

And just for further measure, in a pinch has anyone used anything outside the traditional auto fuel? Avgas? 100LL?
 

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I'm planning an extended trip to northern canada next month and from what I can tell, low test is the only option at most of the fill stations in the areas I'll be heading. So my question is: is there anyone on the board who has been running 87 in their MTS1200 for extended periods of time?

I did a search but it seems most of the threads that cover this topic just end up turning into a lesson on how to calculate octane or people debating the benefits, etc... As interesting as all of that is, really what I'm just looking for is if anyone has done 5,000km+ on low test?

And just for further measure, in a pinch has anyone used anything outside the traditional auto fuel? Avgas? 100LL?
No, I have not used 87 for extended periods in this bike (but absolutely in plenty of other high compression sport bikes)....But it should be just fine, there is a fairly big margin built in, and Not everything you buy at the pump is still on spec for Octane anyway, it’s very very rarely tested for octane after production....Very few laboratories outside a refinery has an engine tester.

Yes, I have used 100LL in my MTS, it runs fine, but you honestly cannot tell the difference by seat of the pants....More importantly, do not continue to use it, the Lead will kill your catalytic converter and it’s damned expensive fuel.:think:
 

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I've ONLY used 87 octane in my Multi. When I bought my ST4S from BCM back in 2004, Bruce told me to use this. I believe I asked about this when I picked up the Multi, and they told me 87 was fine.
 

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Old Wizard
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The risk associated with using too low an octane fuel is detonation/engine knock. Without getting into specifics here, if detonation is allowed to persist it can damage an engine. Ducati figured out your engine's octane needs using knock sensors during engine development on a dyno. So, if you haven't changed compression ratio, it is best to follow the factory's recommended fuel octane rating listed in your Owner's Manual.

Canada and the U.S. Use the same fuel octane rating system so the numbers on the pumps are comparable.

If you have no choice, and temporarily have to run a lower octane fuel than the premium grade recommended by Ducati, detonation can be minimized by reducing peak cylinder pressure by using a higher engine rpm. Knock occurs more easily at low rpm than high, so in general, use a lower gear than you normally would.

In particular, you should minimize lugging your engine. Using smaller throttle openings at low engine speeds will reduce manifold pressure and reduce detonation. Drop down a gear when you need to pass or climb. Also, the higher in elevation that you ride the less tendency there is to experience knock.

Avgas can be used but it has its own set of issues. Aviation fuel is specifically blended for aircraft engines. Aircraft operate under very different conditions than automobiles, and the fuel requirements are quite different as well. Aircraft engines generally run within a very narrow rpm range. There's no need for transient throttle response in an airplane because after the pilot does the initial engine run-up, the throttle is set in one position and the rpm doesn't normally change until landing.

Also, airplanes fly where the air is cold and thin, and the atmospheric pressure is low. These are not even close to the conditions your bike will see on the ground. Also, since most piston-driven aircraft cruise at 3,000 rpm or so, the burn rate of aviation gas is much too slow for high performance engines.
 

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I used 89 99% of the time. Put in 91 octane once I think. Never put in 93. It seems to be doing fine but not as many miles as some others on here.
 

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Discussion Starter #6
Thanks, thats great info on the high vs low revs. I wouldn't have thought that myself. The Avgas or 100LL would only be as a last resort. I'm bringing a 2gal rotopax fuel cell with me so hopefully that will extend my range to the point where I don't need to be concerned about running out of fuel before seeing the next fill station.
 

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Octane

The altitude where you operate the bike will also have an impact. You can get away with lower octane at higher altitudes. You can also buy a few bottles of octane boost and take those on trips where you think you can't get high octane gas.

I agree with prior post that engineers thoroughly researched and recommend the optimal octane in the instruction manual, but I suspect this is for "worst-case" conditions and you can probably get away with lower in some areas, particularly if you avoid "thumping" the motor at low RPM's (going uphill especially).
 

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I don't know where you got the idea that Canada does not have "high" test. It certainly does probably everywhere there's a pumping station ranging from 91 to 94 and even higher. I don't know what the compression rating is for the 11* 1200cc engine, but unless it's an actual high compression rating, like OVER 11.5:1, I wouldn't worry about it. My ST3 is 11.3:1, and has always been fed 87 with no problems. :)
 

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Maybe not too helpful, but I just returned from Alaska and you are right, lots of places only 87 octane available. I was on my Super Tenere which manufacture also recommends 91 or higher. Cassair hwy 37 was one, that only had 87, and the mid point (junction 37A) station was closed, had to go to Stewart.

No ill effects, no pinging. It was cool like in 60s or less and you will be only cruising in most cases, maybe a few passes of a string of RVs, so no problems.
 

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Avgas can be used but it has its own set of issues. Aviation fuel is specifically blended for aircraft engines. Aircraft operate under very different conditions than automobiles, and the fuel requirements are quite different as well. Aircraft engines generally run within a very narrow rpm range. There's no need for transient throttle response in an airplane because after the pilot does the initial engine run-up, the throttle is set in one position and the rpm doesn't normally change until landing.
While this may be true of fixed wing, it is certainly not the expected behavior of rotarywing recip aircraft. They do indeed depend on being able to rapidly change throttle to keep rotor speed constant with differing pitch. Both use the same fuel.

.02
 

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Old Wizard
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The altitude where you operate the bike will also have an impact. You can get away with lower octane at higher altitudes.
Just to follow-up on this point; our bikes have an atmospheric pressure sensor that the computer uses to monitor air density and to reduce fuel as the air becomes less dense at altitude. It's programmed to reduce fuel but not enough to maintain a constant air/fuel ratio, so you end up running rich at altitude.

An engine that runs rich is less likely to knock.

Conversely, an engine that runs lean will have a need for a higher octane fuel to prevent knock. I mention this because in recent years Ducati has delivered an engine design that develops power at leaner fuel mixtures, mainly in response to environmental law requirements. This would explain why Ducati's recommended minimum octane requirements have risen over time even though compression ratios have remained constant.

One final point. You will hear claims that running a lower than recommended octane fuel in Ducati has been done with no apparent problems. This is not the same as claiming that the engine doesn't knock. Frankly, how you would know it was knocking, given the racket that these bikes make, is a puzzle to me.
 

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While this may be true of fixed wing, it is certainly not the expected behavior of rotarywing recip aircraft. They do indeed depend on being able to rapidly change throttle to keep rotor speed constant with differing pitch. Both use the same fuel.

.02
SE84, your correct they are the same fuel, in fact if people compared the specification of aviation gasoline to automotive gasoline most would be surprised with how similar they are…there are even circumstances where you are permitted to use automotive gasoline in aircraft. Aviation fuel is a much better product and far more tightly controlled because of safety of flight issues and operating environment, like Freezing Point (not a specification of Auto fuel) and cold start performance. While automotive is driven by environmental and cost factors. But the majority of all the differences do not negatively impact automotive engines. They are different to accommodate the special requirements for aviation. There are differences in specifications based on individual requirements, the 2 most prevalent for our purposes (motorcycle use), is excessive knock and volatility/performance. The knock rating is addressed with the octane # and has very little effect from a drivability standpoint, (but SUSTAINED detonation will cause engine damage)... while the volatility generally addresses performance and cold start issues. Those are controlled through distillation and reid vapor pressure specifications. Transient throttle response is not a factor for either fuel, there is not specification control to address this in either specification. The closest in something called drivability index, which uses distillation points in a calculation to provide an index, but at a quick glance, Aviation would have a better DI anyway. The bottom line is in all but the most VERY extreme conditions aviation fuel could be used in our bikes. (the converse is also true, in that automotive fuel used in severe extreme conditions would not be appropriate for our bikes). The margin of error engineered into engines (aircraft/automotive) as well as the specifications for petroleum grades are wide and established addressing this.

Would I use aviation fuel in my MTS routinely…NO, there are many reasons why automotive fuel is a better option. However, would I use aviation fuel if needed in a pinch, YES without worry. As for 87 Octane in a MTS, Given my understanding of the field, Yes it is fine in all but the most extreme situations. I would not give a second though to using 87 octane in general use. I understand what your actually receiving at the pump and what “use” limits are for these specifications.

WHEW.....That was fun;)
 

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This would explain why Ducati's recommended minimum octane requirements have risen over time even though compression ratios have remained constant.
I suspect that Ducati, design engines to run on 95 Ron as the minimum legal standard for petrol (gas) across Europe is 95 RON
 

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Old Wizard
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I suspect that Ducati, design engines to run on 95 Ron as the minimum legal standard for petrol (gas) across Europe is 95 RON
I think you mean that 95 RON is the legal minimum octane rating for Premium grade fuel, not that it's the minimum octane fuel available at the pump.
 

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I have not read anything one way or another, but here lies the real question: Does the engine have an anti-knock sensor? Most modern engines do. These will adjust the timing to prevent knocking. The end result is less horsepower as the timing is not where the engine was designed for. So, assuming the bike has an anti-knock sensor, you can run the lower grade gas without damage. The only result would be that you would lose some hp. If anybody has insight as to whether or not this engine contains an anti-knock sensor, please speak up.
 

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I think you mean that 95 RON is the legal minimum octane rating for Premium grade fuel, not that it's the minimum octane fuel available at the pump.
Nope, 95 Ron is the minimum octane rating you get at the pump in Europe, 97 Ron + is considered premium fuel here.
 

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The rating at the pump is the minimun rating , it MAY have a higher grade fuel , When shipped thru pipeline they ship batches no Pigs(barrier to seperate different fluids) between batches,
So at the depot where the gas is recieved into large tanks from the pipeline ,(where the transport trucks load fuels) , some Premiun fuel is filled into tanks of Regular until the tested product is rated Regular.

The fuel mix is not loaded into the premium tanks, at the depot, untill it registers Premium ...
So some regular is actually a higher grade ...

You can get different fuels from different refinerys , that are name brand say SUNOCO that is acutally made from a different named refinery..
The fuel just has to be of a certain base Quality...
The gas you buy is not ALWAYS the same exactly quality , but meets specs.

And where there is not a dedicated Premium pump you may get regular into your gas tank until the Premium starts flowing .
This is where you let your buddy get his gas tank fillrd first so you get the full Premium...

Personally I would not worry about getting a tank or 2 of lesser grade fuel every now and then...
 
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