[steevg]

Hey guys,
I was told when I bought my (imported) 2003 ST, that the higher grade 98 octane (here in NZ) fuel, was the best to use. But other experienced bikers advised to try each (98, 95 & 91) and see how it ran on a longish run - done all of these, and to be quite honest, there's not much to choose from - performance wise - between any of them.

I didn't get a user's manual with the bike, so have no idea of Triumph's recommendations.

Any comments or advice here would be most welome - the bike world has moved on heaps since I last rode back in the early 90's - and obviously the fuels has too!

Ta!
Steve

 

[Cuyose]

Manual recommends 89 or above. As long as yur engine isn't pinging from pre-detonation, you are fine.

Octane doesn't give you more power, it's just less volitile, alowing it to be run in the higher compression engines.

If it's running fine and the engine isn't knocking, than anything higher i just costing yu more money. The additives in the fuels are the same for the different octane ratings as mandated a while back, so buying the "super" or "premium" for the addatives isn't doing you any good.

 

[steevg]

Thanks for the reply,
Nope . . . . no apparent "pinging" etc., but I do notice - whichever fuel I use - that I frequently get a very small amount of "popping" when I release the throttle. Doesn't sound like a major problem, but then I'm not an expert.

Is this normal?

Other than that, she runs real smooth !

Ta!
Steve

 

[Cuyose]

That's entirely normal. Most bikes are all mapped a bit lean, especially on the idle. When you are closing the throttle it transitions to the idle circuit(carbed engine), ecu in fuelinjected changed this on new bikes I guess, and since its a bit lean you get some of that popping.

Some people like it, as long as its not a huge M-80 backfire you are all good. You can use the tune-boy from what I hear to richen up the idle miture a little and decrease that.

I am new to the fuel injected world, but the symptoms are the same, carburated or injected, as regards to the popping on deceleration.

Enjoy the ride!

 

[DaveM]

steevg,
Kiwi bro, you should use a minimum of 95 Ron.

You should use NZ or Oz 95 or 98 octane rated fuels in your Sprint. The NZ and Oz manual states a minimum of 95.

Which in your or in the case of Australia is NOT 91 octane.

Your motor has been designed to run on your 95 or higher octane fuels.
With the exception in New Zealand and Australia of Shell Optimax or now it is called V-Power here.

The later is too dense and has a lot of sulphur in it which clogs fuel injector jets on pre 05 sagem equipt machines after prolonged use.
I am unsure if it is ok in the Keihin injection system or not fitted to the 1050 models.

I always use BP 98 or Caltex 98 if available or any premium 95 octane fuel.

cheers,
DaveM

 

[steevg]

DaveM,
Hey thanks for the repliy - I'll make sure to use the 95 Octane available here in NZ, in future !

Cuyose,
thanks also for putting my mind at rest about the "popping" - I must admit to being a little concerned, as I was with an apparent chain noise from the engine, but I'm guessing it's me being a little too fussy and noticing the noise of the chain running over the front sprocket. Never really noticed these things before - must be getting old and cranky!

Have a great New Years!

Steve

 

[duckie]

If we should be using 98, it leaves us in California with a big problem... unless there is more to the octane number than just the number because the only place you can get anything greater than 91 is at a race track... on the street, the highest grade is 91 and the lowest is 87...!

 

[DaveM]

duckie,
there is a thread about this.

I think your fuel in the USA is different, most likely better than ours!

Do a search you'll find it. I can only speak for the NZ and Australian fuel rating system. Our manuals here state minimum 95 Ron.

cheers,
DaveM

 

[Stlakid]

From Internet

Measurement methods

The most common type of octane rating worldwide is the Research Octane Number (RON). RON is determined by running the fuel through a specific test engine with a variable compression ratio under controlled conditions, and comparing these results with those for mixtures of isooctane and n-heptane.

There is another type of octane rating, called Motor Octane Number (MON) or the aviation lean octane rating, which is a better measure of how the fuel behaves when under load. MON testing uses a similar test engine to that used in RON testing, but with a preheated fuel mixture, a higher engine speed, and variable ignition timing to further stress the fuel's knock resistance. Depending on the composition of the fuel, the MON of a modern gasoline will be about 8 to 10 points lower than the RON. Normally fuel specifications require both a minimum RON and a minimum MON.

In most countries (including all of Europe and Australia) the "headline" octane that would be shown on the pump is the RON, but in the United States and some other countries the headline number is the average of the RON and the MON, sometimes called the Anti-Knock Index (AKI), Road Octane Number (RdON), Pump Octane Number (PON), or (R+M)/2. Because of the 8 to 10 point difference noted above, this means that the octane in the United States will be about 4 to 5 points lower than the same fuel elsewhere: 87 octane fuel, the "regular" gasoline in the US and Canada, would be 91-95 (regular) in Europe.

The octane rating may also be a "trade name", with the actual figure being higher than the nominal rating.[citation needed]

It is possible for a fuel to have a RON greater than 100, because isooctane is not the most knock-resistant substance available. Racing fuels, straight ethanol, Avgas and liquefied petroleum gas (LPG) typically have octane ratings of 110 or significantly higher - ethanol's RON is 129 (MON 102, AKI 116). Typical "octane booster" additives include tetra-ethyl lead and toluene. Tetra-ethyl lead is easily decomposed to its component radicals, which react with the radicals from the fuel and oxygen that would start the combustion, thereby delaying ignition.

So in Europe and Australia/New Zealand you should use 95 minimum as DaveM states. 98 won't hurt or make it run any better.
Here in the states you should run 89 minimum. 91/92/93 (depending on your state) won't hurt or make any difference here. I have run my bike on all three grades here to see the differences. You CAN run the bike just fine on 87, just go easy on the take-offs and don't load it hard. 89 actually seems to run the best giving slightly crisper throttle response. 91 just lets you load the engine harder before it will ping. You are probably in the wrong gear anyway at this point. You CAN however get ANY grade to ping if you load the engine to hard. I run 89 most of the time. When the heat of summer is here I will usually get the 91 just to have a bit more room as I tend to load the engine rather than race away from most lights.



[ This message was edited by: Stlakid on 2006-12-28 02:58 ]

 

[LoVel]

Thanks for the quick lesson Stlakid. Very informative. I knew if I was using the 93 I shouldn't have a problem but it is good to know the reason for the difference.

 

[Cuyose]

Again, I was unaware of the out of States different ratings, It would be nice if they were different't that they could be WAY different! Like 89 equating to 189 or something , not 97.

At any rate, like whatthe previous posters said, 89 is recommended and as long as you are't pinging you are good.

 

[duckie]

Thankyou both DaveM and Stiakid for clearing that up - having moved to California from the England a while back that has always puzzled me

Earlier this year I did a trackday at Infineon Raceway and near the end of the day I had to fill up at the track. Seeing a empty pump I pulled up, put my creditcard in and started pumping. I was too busy watching the other bikes on the track to pay close attention to what I was doing until halfway through filling up when I noticed that it was v expensive (like $9 a gallon compared to $2.6 a gallon on the street) so I stopped pumping after having put in 2 gallons. It was at that point I noticed that it was leaded fuel and had an octane rating of 110! DOH! :-D
Afterwards I pull up to staging area in the pits and say to my friend who had filled up just before me on another pump - "Those pumps only have really high octane gas which is bloody expensive!" to which he replied with a massive grin on his face "That's why everyone else was lining up for the pump I was at - it's the only pump with unleaded 91 octane gas the others have race fuel!" :blush:
So I was expecting that my bike (suzuki sv650s) would pick up a lot quicker but it didn't seem to run any better or worse (thankfully) - maybe it was a bit smoother under hard accelaration but that was it - I guess that goes to show that putting in too high octane only helps to drain your wallet quicker...

 

[Stlakid]

The ONLY thing the leaded fuel will hurt is the catalytic converter. I assume that if you were doing a track day you already have an after market can on it so no harm done. ER, except to your wallet!
Just be glad you're not running your original '69 Chevelle with a LS6 and need 22 Gallons of the stuff!

 

[dart330]

I usually run 91 [(R+M)/2] here in Missouri as most of the 89 available contains 10% ethanol while the 87 doesn't.

They also just passed a bill requiring all fuel (in MO) in the near future other than premium (91+) to contain 10% ethanol.

Needless to say I dislike this bill and will continue running premium in all of my vehicles. If I want to burn crops in my engine I will buy a diesel.....