Petrol Octane rating

[Deano]

In NZ petrol is Octane rated and is available in two grades. Unleaded 91 and unleaded 95. Triumph recommend using 91. I have recently found out (by mistakenly putting the wrong go juice in at the pumps) that 95 makes my bike go better. I thought maybe I could be doing some damage. 95% said some motors don't like the extra heat and suffer damage, but upon contacting the Triumph dealer he said go for it. He said I will get a bonus of more kms per tank, increased power and it has stopped a little hunt it had at a certain steady beat. He also enlightened me that Triumph has to state the lowest Octane rating it will run at in any given country. 95 is more expensive than 91 here but I think its well worth it. Any comments?

 

[Texas94fs]

meh, I've run all from 89-93 and notice no difference what so ever, I'm on a carbed bike though, maybe fuel injection would change that? It's your money, doubt you'll see a mileage increase per tank though.

 

[qwenzel]

I run 87 octane (regular in the US), cheaper and no difference from the other octanes.

BTW you won't get any better mileage from the 95 octane than from the 91 octane.

 

[Deano]

meh, I've run all from 89-93 and notice no difference what so ever, I'm on a carbed bike though, maybe fuel injection would change that? It's your money, doubt you'll see a mileage increase per tank though.

Mines a carbed bike as well Texas, and your probably right about the mileage thing, I did doubt that a bit.


But there is definetely a difference in the performance that I can detect. Octane rating must make some sort of difference because if I put 91 in the fuel injected guzzi, which is meant to have 95, it dosent like it, runs like a pig. Can anyone tell me why the different Octane ratings and recommendations, and why would Triumph have to state the minimum rating at which the bikes will still run properly, if it didnt make a scrap of difference?

 

[Texas94fs]

some states only get 91 and not 93 or 95

 

[sweatmachine]

A higher octane will net you LESS miles per gallon than a lower one. The difference is probably negligible, but it's true. Higher octane WILL NOT INCREASE PERFORMANCE.

 

[MMasz]

I don’t know about NZ, but in the US we have ethanol in our gas which hurts mileage and potentially damages the engine. I use ethanol free gas in my vehicles and they run better and get better gas mileage (about 2 mpg).

Also, the higher octane fuels may have additional additives/cleaners which improve engine efficiency.

BTW, my wife and I vacationed in NZ about 10 years ago. It was beautiful and is the only place I’d move to if I ever left the US.

 

[FoothillRyder]

There is a reason for higher octane fuel guys. The Scrambler doesn't need it, can't use it, and it's a waste of money to buy it if it's going in a Scrambler; but...

The reason for higher octane fuel is to reduce any tendency a particular engine might have for 'pre-ignition'. Higher octane fuel is LESS volatile than lower octane fuel. These statements about higher octane fuel not yielding more power or better fuel mileage are true - as applied to a stock Scrambler - but may be false if applied to other engines.

Just so we're clear.

 

[Deano]

There is a reason for higher octane fuel guys. The Scrambler doesn't need it, can't use it, and it's a waste of money to buy it if it's going in a Scrambler; but...

The reason for higher octane fuel is to reduce any tendency a particular engine might have for 'pre-ignition'. Higher octane fuel is LESS volatile than lower octane fuel. These statements about higher octane fuel not yielding more power or better fuel mileage are true - as applied to a stock Scrambler - but may be false if applied to other engines.

Just so we're clear.

Thanks for all the info guy's. Two lessons have been learnt by me. Firstly you obviously cant trust the word of a Triumph race tuning mechanic, and secondly I cant trust my senses that seemed to tell me the bike ran better. Not more power or mileage, as he had suggested, but just better?? Back to 91.

 

[Deano]

I don’t know about NZ, but in the US we have ethanol in our gas which hurts mileage and potentially damages the engine. I use ethanol free gas in my vehicles and they run better and get better gas mileage (about 2 mpg).

Also, the higher octane fuels may have additional additives/cleaners which improve engine efficiency.

BTW, my wife and I vacationed in NZ about 10 years ago. It was beautiful and is the only place I’d move to if I ever left the US.

Sorry to hear about the bike being stolen dude. F...n asses. Your comments about NZ are very appreciated, and it is a really good little country to run a scrambler in, lots of those in between type roads that the scrambler seems to love. I think in the UK they call them green lanes.

 

[Mike Britton]

"There is a reason for higher octane fuel guys. The Scrambler doesn't need it, can't use it, and it's a waste of money to buy it if it's going in a Scrambler; but..."
When I bought my '06 Scram back in May, the dealer told me to save my money on higher octane. But, just for grins, I put in a tank full of 89, the middle grade here in the metroplex, and I'm convinced the bike is smoother, and idles smoother. My imagination?
I havn't gone back to 87, as I haven't had a chance to ride much since June.

 

[xy500]

While higher a higher octane fuel may not necessarily increase power on its own, the properties of higher octane fuels can be more desirable. For example, if you were to tune your ignition map for 98 octane, the highest available here from the pump. You would see a power increase, as you can safely run more spark advance for more torque and efficiency. The energy density is also different. But at the end of the day, I run premium fuels because they can sit for longer without deteriorating or varnishing up the fuel system than regular.
Sorry to burst your bubble, but If an engine is tuned for a higher octane fuel. You will see a power and economy increase by using the right fuel. But most engines are tuned for lower octanes.

 

[sweatmachine]

Thanks for all the info guy's. Two lessons have been learnt by me. Firstly you obviously cant trust the word of a Triumph race tuning mechanic, and secondly I cant trust my senses that seemed to tell me the bike ran better. Not more power or mileage, as he had suggested, but just better?? Back to 91.

Also, you can spare the mis-use of apostrophes. No need for them on plural words. Remember, like with bikes and octane, words need less than you think.

 

[Deano]

"There is a reason for higher octane fuel guys. The Scrambler doesn't need it, can't use it, and it's a waste of money to buy it if it's going in a Scrambler; but..."
When I bought my '06 Scram back in May, the dealer told me to save my money on higher octane. But, just for grins, I put in a tank full of 89, the middle grade here in the metroplex, and I'm convinced the bike is smoother, and idles smoother. My imagination?
I havn't gone back to 87, as I haven't had a chance to ride much since June.

Have you got any pictures you can share of the flat tracker? Mmmm

 

[Mike Britton]

Deano, I do have some pics, but my computer has sh&T itself, and I can't get image shack to work. It's my avitar, but that's too small an image.
The old monster looks kind of beat up in the photo, as it's time once again, for a restoration. As is typical of some of us, parts have been robbed off it to keep other bikes alive. As soon as I can get my granddaughter over to help me, I'll get this P.O.S. working again.