Super unleaded
 

I'm sure this has been done to death before on here but i thought i'd share my experience of using it with you all.

For 2k i ran my Tenere on texaco or tesco fuel and had real problems with the bar vibrations. They were so bad that after my daily hour ride to work my finger tips were numb. I used to call my wife just as i got off the bike while walking in and using the phone was hard as i could not feel the ends of all my fingers for some 20 mins.

Also while doing 60mph in 4th at 4k revs the bar buzzing was so bad that i could not sustain that speed/rev combination for long.

So last friday i tried a tank of Vpower. For the first 200 miles there was nothing to report. Then while riding home from work on Monday it all stopped....the bar vibrations suddenly dropped to a level that i hardly notice them. This has continued through a second tank of Vpower. I am going back on cheap stuff tonight to see what happens.

I'm not getting any more power but everything is suddenly so smooth and i mean in a big way. The Ten now feels like a twin not a single. The bar vibes were so bad i was trying to sell her but now i won't as it's all so good.

On ABR i ignited a good debate on this with some saying that Vpower can't have made this effect but i can tell you that something changed on the bike in a big way and the only differance was the fuel.

So please tell me what you think of Vpower or super unleaded?

Mike

People on ABR saying something that's correct? Never? :D

I've been using super unleaded for several months and agree there is a noticeable improvement. The power delivery from low revs is improved and the engine is generally less agricultural...give it a try

Hypothesis?

I'm off to the pub, I'll have a think about it there....

Well dunno, I have tried VPower diesel in the car and it did seem smoother. In the XT I use standard fuel and use STP or similar additive every month or so and this seems to work for me. I have never tried VPower in the bike but I am sure it is "better" than standard fuel as it has some additives.

"It's more expensive, it must be better"

I recall reading that 97RON+ unleaded gives an ever so slightly richer AF ratio on the dyno, but nothing hugely significant. In fact there is precious little concrete evidence out there to prove running SUL opposed to UL makes any real difference.

On an engine management system without knock sensors (like the XT) it is going to make much less of a difference. The real benefits of high octane fuel are that you can run more advanced ignition timing and higher compression ratios to get more power, but if you aren't going to do that, then its advantages are questionable. There is another valid argument to suggest that "expensive" fuels have more/better additives to clean the engine and lubricate valves, but that's muddied by all the sales hype the fuel companies give about their "super" fuels.

Despite this, I do find my bike runs a tad more smoothly in the lower reaches of the rev range on SUL. Now whether that's in my head, or for real, is a open to debate! However, what I would say is, if you and your bike "feel" better on SUL and you can afford it (whatever the reasons/logic behind it are) then you may as well use it. If you can't feel any difference, or can't afford it then don't bother!

Well, I've discovered Tesco Momentum 99 Octane recently...


Used to get 57/58 mpg...

This has now become 63 mpg...

I haven't changed the way I ride, just the petrol.


The figures speak for themselves.


It's �1.38 / litre near me...

Found this.... of interest?

[Well! In The Beginning there was Carbon and Hydrogen.

These got together in accordance with rules forged in the Big Bang (yes, really!) to make methane, one carbon atom with 4 hydrogens stuck on.

A bit later, (only 4000 million years) other atoms started getting together and finally came up with Life, a self-reproducing chemical mix. The reproducing bit was quite fun, but after 600 million years even that gets boring.

So, a more or less intelligent life-form invented The Car and the Motorcycle, the ultimate boredom cure. This was, and is, powered by the Internal Combustion Engine, which must have fuel.

Methane is a fuel, which means it burns in air to produce energy, but unfortunately its a gas; a tank-full would propel a Honda 50 for about half a mile.

But! Methane had not been idle since the formation of planet Earth, and had joined up with more carbons and hydrogens to make chains called hydrocarbons. Well, they werent called that at the time. They had to wait for a life-form to evolve that liked giving things names, and a hundred and 20-odd years ago chemists had to learn Latin, so they called the one with five carbons pentane, the 6-carbon one hexane, then heptane then.wait for it the 8-carbon one octane and so on. (If we were naming them now the last one would be called eightane so you would need 95 minimum REN for your engine.)

All these things were liquids, very thin and volatile, and pure concentrated energy. The Hildebrand and Wolfmuller (rough 1894 equivalent of the Honda 50) now did 100 miles to the tank full.

Unlike water, these liquids dont stand around in lakes. They are hidden underground in porous rock so you have to drill for them. The old name was petroleum meaning rock oil but this was soon shortened to petrol. The petrol came out of the wells mixed with heavy oil, so it had to be distilled off in an oil refinery.

Early on, the pale coloured stuff that evaporated easily and caught fire very easily was sold as internal combustion engine fuel. It was a simple as that. Octane Number hadnt been invented, but in modern terms this light petroleum fraction was about 50 Octane. Now we all know that in the GCSE Science engine The Piston squeezes the air/fuel mixture, then The Spark Plug ignites it to produce The Power Stroke.

Octane. Now we all know that in the GCSE Science engine The Piston squeezes the air/fuel mixture, then The Spark Plug ignites it to produce The Power Stroke.

The trouble is, with 50 octane fuel if The Piston squeezes too much the heat generated by compression makes the stuff Go Bang prematurely before The Spark Plug gets a look in, giving a Power Stroke with as much push as a fairys fart. This is why early engines couldnt use compression ratios above 4 : 1, and 10BHP per litre was seen as hot stuff.

Engines improved but petrol didnt and even some time after WW 1 a touring 1000cc engine only turned out about 25BHP, and a hot-shot Sport version with the latest overhead valves would need a good tuner to get 50BHP.

So finally some effort was made to stop primitive petrol going bang too soon, and a variable compression engine was invented for research. (The CFR engine, as used for finding Research and Motor Octane Numbers, RON and MON, to this very day.) Early on researchers found that the bung in the CFR head could be really screwed down if a heavy liquid called TEL (tetra ethyl lead) was added. This was really effective and cheap, and allowed the straight petrol to be upped to 90 or even 100 octane, and a whole load of exciting high-power engines were designed around these fuels.

This leaded fuel survived into the late 1990s, but much earlier an amazing discovery had been made. The shape of the petrol molecules was very important. Octane if the straight eight version with 8 carbons in a row had an octane number of 25. It was only the mutant octane with 5 carbons down the middle and the others sticking out from the sides that gave the best results at high compression. (This special octane is still used as a standard for 100 octane. Proper name is 2,2,4-trimethyl pentane.)

Today, petrol is really a synthetic fluid built up from oil industry feedstocks. Very little of it is unmodified distillate from crude oil. It is tailor made to include the best compression-resisting molecules so that no poisonous and polluting lead compounds are needed to reach 95 or even 98 octane. Nothing much is added, apart from a touch of detergent to keep the engine top end clean. Quite a lot of petrol now has 10% renewable alcohol as a planet-saving gesture, but this also improves the octane number (by about 1 ) so theres nothing wrong with that.]

Also I'm, told that apparently the V power stuff, with different RON values, is different from regular petrol. It has less volatile stuff which helps reduce any predetonation. The important thing to note is that it is made to a different specification at the refinery, it's not just additives.