Which octane

[DarkMonster620]

Shell is a Ducati racing sponsor. 

Out of an official Ducati service manual:
Engine oil
A good quality engine oil has special properties. Use only a highly detergent engine oil with certified SE, SF or SG or higher service ratings as marked on the container.

Here in the US, Shell is one of the few gasolines that meets "Top Tier Certification"
http://www.toptiergas.com    but, as ducatiz stated, this may not be an indicator of  the product Shell is selling in Australia.  Shell is also selling the gasahol (E10) we are complaining about.  Avoid it!!

$$

Good point triple j, howie... That's tjhe main reason behing my changing to Repsol...

[junior varsity]

So why do Ducati engineers use Shell? Why does Ducati Corse use Shell? Why does Ducati even recommends using all Shell[oils, susp fluids, brake fluids, fuel, chainlube, ...]? According to owners manual, this is.

Also, Ferrarri.

Unless a Shell Employee tells me that he won't use his own product, I would listen to nobody as to which gas station is better - only that off-brand gas is taking a risk.   (Kind of like, if a fast food employee told me NOT to eat the food that comes from his store, I'd listen otherwise he's just talkin' to move air).

[jasaretta]

So why do Ducati engineers use Shell? Why does Ducati Corse use Shell? Why does Ducati even recommends using all Shell[oils, susp fluids, brake fluids, fuel, chainlube, ...]? According to owners manual, this is.

He did say definitely use Shell oils etc but not fuel. More tomorrow.

[junior varsity]

That's silly. They work in concert with Ferrari and even use the Ferrari's in the advertising. It works fine in those more complex motors, and it works fine in my 2 valve incredibly simple, 2 cylinder motorcycle. Its fuel. It goes boom in a cylinder from compression and a spark. So long as its not cut with a bunch of rubbish fuel at the discount fuel-center, it provides the same amount of go-fast, and the only remaining element is "what flavor detergent do you like the marketing of better?"

[ducatiz]

and the only remaining element is "what flavor detergent do you like the marketing of better?"

when i was in college and worked at the Circle-K (the one at Highland and Southern), one of my jobs was to "stick" the gas tanks to measure levels.  we had a single ruler to do it, it was 20 ft long.  the first tank was with a dry stick, but the other 2 we had to use the same stick.  my shift was usually 10pm -6am and it's hard to see the next wet level in the dark.  boss told me to use Comet powder on the stick, then put it into the gas tank and pull it out and see how much washed off.

yep.  Comet.

[junior varsity]

that helps clean the valves, right?

[ducatiz]

that helps clean the valves, right?

actually, it settles and sediments in a float bowl and hardens.  they eventually got in trouble over it and it turned out to be the dumbass who was my boss.  he was let go.

[junior varsity]

but your valves would be sparkly comet clean, right?

[ducatiz]

but your valves would be sparkly comet clean, right?

rofl, fortunately it didn't get past the carb (this was a long time ago) so it only necessitated replacing the carb.  fun stuff.

[Popeye the Sailor]

Also, Ferrarri.

Unless a Shell Employee tells me that he won't use his own product, I would listen to nobody as to which gas station is better - only that off-brand gas is taking a risk.   (Kind of like, if a fast food employee told me NOT to eat the food that comes from his store, I'd listen otherwise he's just talkin' to move air).

From my understanding, most of those off-brands buy from the name brands. You just don't get the same advertising.

[hackers2r]

So...looking more at this topic.  In my manual, Ducati states that 95-98 RON should be used which converts to 91-93 US.  Which one am I better off running?  Considering I live in hot-as-hell Miami, am I safer to run the 93 to avoid detonation?  Or am I simply over thinking things and just run 91? 

[Popeye the Sailor]

Run the lowest octane possible without pinging.

If it doesn't ping, it's fine.

[DarkMonster620]

hackers2r,

You live in Miami, I live in Panama, same situation, if you read a bit further back on the thread, everyone said to use the lower octane, which here translates to 91AKI or US...
If I use 91 oct in 95*F plus 90% humidity, the bike will sputter all the way to Borno Panigale and back... Telling you this since your weather and mine are almost the same...
If fuel light comes on, and no 95 avail, I'll only put in no more than $1 worth of 91, don't know why this happens but happens...

To the rest of the guys, somehow my bike, behaves a bit different than the other 620s, the only time a Italian tech was here, my bike was in the shop and he said 'here in Panama you can use 91 oct since is the equivalent to 95RON...' then my bike was 'tested'[as was another 620 in the shop], he was, impressed on how my bike had behaved with the 91OCT[sputterd, made noises, ...] and then how it behaved with 95OCT[as normal as is gets], he told me 'it seems you bike only want to run 95OCT so you must only use 95OCT and both heads have an "S" stamped on them, are these the 'good' heads or ....

[hackers2r]

Well, I decided to experiment yesterday.  Siphoned out 2 gallons of the Shell 93 octane that was in the tank and ran it till the gas light came on.  I then pumped just over 1 gallon of Shell 87 octane in and...bike is running fine so far.  I've tried everything to hear something bad; 3rd gear at 30 and just layed on it, highway tests, etc.  Haven't heard ANYTHING bad.  Also been tried in the extreme heat of the day and also the night.  I'm gonna keep running the 87 and see how it goes.  One observation though is that when laying on it in 3rd at 30, it really is smoother than it was with the 93. 

[koko64]

Been reading with great interest.

I have JE hi comp pistons in my carbed 900 Monster. I have retarded the ignition about 3-3 1/2 degrees at the flywheel pickups. I have tried 95 RON fuel with no noticeable knocking/pinging but would guess that with the standard ignition timing you will have to run 98 RON to be safe. I am not 100% secure in running 95 RON however...I am a little nervous doing this. These JE pistons were machined down a little to get the compression closer to 10.7 : 1. This and the retarded ignition could be give me the safety margin to run 95 RON. I will ask Brad Black about this next time I visit his shop.

The Bikeboy site talks about dramas with too high compression, related fuel octane requirements and ignition timing in carbed Monsters. It is for the Australian context in relation to the old carb two valvers with old style ignition. Interesting reading.

Most of my riding mates (buddies) use 98 RON citing smoother running but is this just the placebo effect?

I recently ran 95 RON and had rough running, but wasn't sure if it was just a bad batch of fuel or if some Ethanol was snuck in there affecting things in some way. I will have to run 95 RON over a longer period of time to see if this is a consistent thing.

It seems our experience in Australia is different with Shell 98 RON not having the best reputation in motorcycle use here, while in the US it's possibly one of the better fuels? This has even been mentioned in motorcycle magazine tests where the Shell 98 RON was cited as the cause of rough running, backfiring and plug fouling (Australian Motorcycle News test of a 1098).
This has been my consistent experience in four different motorcycles; a ZX6R, VFR 400, M900 and SL900. Why, I have no idea. The symptoms are like a bike running way too rich. All the bikes ate plugs (fouled) when I used the Shell 98 RON. I want to use Shell because the gas stations are everywhere, but I have to use BP (not too popular at the moment in the US!), Mobil and Caltex.
Now understand that my bad experiences are with the Shell 98 RON, so I may try the Shell 95 RON. I have used the other 98 RON fuels with no ill effects. Maybe the Shell 98 RON is an actual higher octane compared to the other brands of 98 and not completely combusting? Maybe it has a unique additive? It is all quite perplexing.

I'm starting to wonder if our Australian fuels are inferior in knock protection and we have to buy the fuels advertised as "premium" to get the same protection as regular US fuels?

I want to use the lowest octane rating I can get away with due to the aforementioned reasons in this thread. I wish I could use 89/91 RON, but I get knocking/pinging.

This forum needs a fuel expert (like George was with oil) to educate us all.