octane?

[graeme0309]

Petrol standards 97 98 100 (levels of Octane)

I stopped my TLV650 (Alp) outside the Lamborgini factory where 100 octane was available at the pump.

And when I topped it up with 100 I swear the bike rode like a dream.

I was fully loaded with me and about 65kilos of weight in the panniers (I am 125kilos myself).

Anyways, what a joy. I thought I was floating and for the next 50kms I simply thrust along the strada. Torque was amazing. Purred like a kitten.

Now, other moto mates of mine at the Ace Cafe told me that they "doubted" that I really would have noticed the difference of 100 octane. But I swear, it was marvellous. Just marvellous.

So, does 100 octane make a difference? Can it make a difference to a 650 Alp?

[Snaphappy]

Yes

it burns better for the want of a simple description.

[StumpyFingers]

100 Octane is designed for high performance engines so when you were loaded the higher Octane would improve the power of the engine to a point where it is noticeable.

[edteamslr]

On a Compression ratio of 9.2:1 ?

Higher octane ratings means the fuel requires more activation energy before the chemical reaction takes place - i.e. is harder to burn. A given engine is designed to run on a given fuel octane. Being loaded up makes no difference to the compression ratio.

General quality (age etc..) - now there is a possibility.

[graeme0309]

Originally Posted by edteamslr

On a Compression ratio of 9.2:1 ?

Higher octane ratings means the fuel requires more activation energy before the chemical reaction takes place - i.e. is harder to burn. A given engine is designed to run on a given fuel octane. Being loaded up makes no difference to the compression ratio.

General quality (age etc..) - now there is a possibility.

What I was thinking was, by making the comment about being loaded up with so much weight was this - with the bike being so heavy in proportion to an almost negative effect (I am guessing) between 97 and 100 that I wouldn't have felt any power surge.

My buddies said nope, 100 wouldn't have made any difference. Maybe with a nice lightweight performance track bike but not an old banger like mine, loaded to breaking point having been round Europe for years and having been abused and slapped about.

But I beg to differ............... the feelign was superb. When I hit the road with a full tank of 100 I was like "wha, oooooommmppphhhh!"

[Kymmy]

I had one guy who said the same, one time filled his bike up with a very high octane rated fuel and said his bike rode better going home than it did going to the event..

Until we reminded him that home was downhill!!!!

[edteamslr]

You hadn't just come down from the Bologna hills had you, by any chance. Or alps to the north?

This is either altitude or additives. Octane would have very little difference.

[graeme0309]

Yeah, I had just come down from the hills.

What does the altitude do to driving conditions?

And why would petrol stations have different types of additives?

[edteamslr]

Simply the air pressure (static) is higher at sea level and diminishes with altitude. Each cc of air will have a greater concentration of oxygen at low altitude.

With fuel there is more than one way to skin a cat - each of the oil companies will have their own ideas of what meets the consumers' needs for their fuels, how to market them and how to meet that demand. Different geographies, legislation and other needs will dictate what is in your petrol.

[Kymmy]

Originally Posted by graeme0309

Yeah, I had just come down from the hills.

What does the altitude do to driving conditions?

And why would petrol stations have different types of additives?

Each petrol distributer (BP, Shell, Esso, Texaco) have different fomulas that they add to thier petrol and claim it to be cleaner, greener and give more MPG..

As for altitude the engine needs air to mix with the petrol in a specified ratio.. Higher altitude means less air than a lower altitude, if you take your bike up on some continental plateaus they suggest that you alter the carb needles to bring the ratio more inline with the rarified air. Even just a few hundred feet can seriously mean the difference between your bike running too rich, too lean or just right