Page 1 of 4

Higher octane or not?

Posted: Wed Apr 19, 2017 3:03 pm
by melpotter
I'm no mechanical expert but I know there are several Muppets who are, so my question is

'is there any advantage to be had in filling up with a higher octane fuel such as Tesco momentum'?

Considering the claims of cleaning your fuel system I'm particularly wondering if it might help with the slight hesitation I find when opening the throttle from around 20 - 25 mph?

Thoughts?

Re: Higher octane or not?

Posted: Wed Apr 19, 2017 3:16 pm
by SH125Paul
Nope... Not really... But a tank full and a good run wont do any harm...
More likely to be a dirty air filter or spark plug...
Or the ECU settings to get the scoot through emissions testing...

Re: Higher octane or not?

Posted: Wed Apr 19, 2017 3:24 pm
by Bluebottle
Octane rating isn't a power rating (apologies if you already knew that)
It has the same amount of energy in it.

High octane values allow you to compress the fuel more without it igniting, that is why it is associated with high performance engines. It actually slows the burn down.

Unless you have a high compression engine (Ferrari, full blown racer) you won't get any benefit.

It will probably waste fuel and leave partially burnt muck in your motor and exhaust.
In the worst case scenario you can burn valves because the fuel burn gets out of time with the valves.

Re: Higher octane or not?

Posted: Wed Apr 19, 2017 5:22 pm
by Scootypuff snr
melpotter wrote: 'is there any advantage to be had in filling up with a higher octane fuel such as Tesco momentum'?
Thoughts?
Its an old argument but I wouldn't fill up with any supermarket fuel by choice but will in an emergency and make sure I use branded fuels by half a tank.

They say you get more mpg with higher octane fuel but as it costs more that's a negative case IMO.

If you look at all the new euro 4 compliment bikes in the showroom now the fuel tanks now have an E10 sticker instead of unleaded (which I assume will be more available in the UK, as Europe) which can cause knocking in bikes older than 2007 I think it was.

If your suffering hesitation is it your particular bike (some brands are known for such with fi) or something simple such as spark plug, valve clearances or lambda sensor.

Just my pennies worth

Re: Higher octane or not?

Posted: Wed Apr 19, 2017 6:21 pm
by Drago
I've only used standard 95 unleaded with my Joymax so can't comment right on that but
with my Daelim S1 I've used 95 (esso), 97(esso) and 99(Tesco). I had slightly better mpg with
the higher octane fuels but performance was no better. BUT 97 the super unleaded was more expensive,
making it more expensive to use over standard unleaded, despite the mpg gain. Tesco 99 stuff when I used it was not much more than 95 unleaded from Esso. But the Tesco pumps are dodgy I'm my opinion, sucking a lot more back as I put in '8.5L' rather than the usual 7.2L at Esso, again this was more expensive than normal unleaded from esso. I've used Tesco standard unleaded in the past and found it to reduced mpg quite a bit.

Like bluebottle said, higher octane fuels don't ignite as quickly, the fuel itself won't provide more power unless of course it's used in a high compression engine. I'd stick to just standard unleaded and use a injection cleaner occasionally.

Re: Higher octane or not?

Posted: Thu Apr 20, 2017 2:51 am
by Dogsbody
The main advantage for me in using Esso super unleaded is the fact it does not contain Ethanol. Ethanol absorbs water from the air and gives rise to problems if the fuel is unused for some weeks. It also attacks old type seals, pipes and taps. Not a problem on modern bikes designed for it but a major problem for older stuff. Ducati lost a class action in America as the plastic fuel tanks were expanding and coming loose on the front mountings. It also affected Triumph and Aprilia to a lesser degree. This was because of the use of 10% ethanol in the states. It also dissolves fibreglass as many have found out to their cost. I use Sunoco R5SR race fuel in my Greeves fibreglass tanked race bike as it is guaranteed ethanol free although it does cost £4 /litre
So if you only use your bike , scoot, lawnmower or whatever occasionally , my advice would be to fill up with super unleaded preferably not supermarket. Dogsbody

Re: Higher octane or not?

Posted: Thu Apr 20, 2017 3:04 am
by melpotter
Drago wrote:I've only used standard 95 unleaded with my Joymax so can't comment right on that
Thanks to everyone for your thoughts, most interesting. Drago do you experience any hesitation on your JoyMax?

Re: Higher octane or not?

Posted: Thu Apr 20, 2017 6:43 am
by Waldorf
I'm a fan of Esso petrol and diesel and use it if I possibly can.
I have done almost since I first owned a car in 1968 - it was the nearest and most convenient filling-station - and favour it if there's a choice.
Like others, I went through a period of using supermarket filling-stations because of lower prices but I am convinced that their fuel is not as good.

I guess it's all down to additives; the more and better they are, the more expensive the fuel.
I ride mostly for pleasure so the few pence extra per litre doesn't worry me; I guess if I was commuting every day I might think differently.

Incidentally, I still have a significant number of Esso glasses. ;)

And incidentally again; there's an Esso station conveniently-placed nearby and close to Tescos so isn't very busy and ................. I can use my Tesco Points card there! :D

Re: Higher octane or not?

Posted: Thu Apr 20, 2017 6:52 am
by Pugwash57
When I bought my Nmax 125 my yamaha dealer said to always use super unleaded because of the mix of ethanol put into standard petrol, so I have.
I have a car thats needs super & I stay clear of super market (super unleaded) as it makes my car pink.

Re: Higher octane or not?

Posted: Thu Apr 20, 2017 7:09 am
by Steve_D
On another forum that I belong to, one of the regulars is a fuel tanker delivery driver, delivering to various supermarkets and named brand stations. He says that only one type of base fuel is pumped into the different brand tanks. To get the 'special' blends V nitro, Excellium or whatever, those additives are added into the tanks by him at the station. He doesn't know what is in them or how much goes in, only that it goes through a small 1/2" pipe and doesn't take long.