Does premium fuel do anything?

[bladerunner]

oddly old shitter of a cg125 used to go like LOADS faster on super unleaded ( well compared to the usual shit slow snail it was) yet non of the 4 fireblades liked it either carb or FI ....some really didnt like super. ...guess with points ignition you could tweak the timing a little to gain advantage but any non mapped jap bike is setup for running on any old crap and didnt like the slower burn
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Current bikes...cbr929, KDX200's, Rd125lc mk2, RGV250's

[weasley]

There are a couple of ways premium fuel can help:

1. Higher RON. This means increased resistance to preignition, which means that you can use an advanced ignition timing; this can give increased power/efficiency through having more of the expansion of the combustion phase happening after TDC. Engines with knock sensors and dynamic ignition mapping can actively hunt the optimum ignition timing, or you could manually adjust the timing for higher RON fuel (with the expectation that you then always have to use it). However, higher RON fuel can also benefit older engines if they have any combustion chamber deposits. These deposits can increase the compression ratio and act as a glow plug, both of which can lead to preignition, which the higher RON can mitigate.

2. Cleanliness. Premium fuels tend to also have higher dosages of detergents and other additives which help clean the fuel system. Fouled injectors give a sub-optimal spray pattern and dirty jets give poor carburation. These deposits can be avoided with better fuel, or even removed if you have previously used lesser fuels. Obviously better fuelling will give better combustion efficiency.

I work in this area. Not in fuels per se, but in the next door office of lubricants. I have a working knowledge of the fuels technology as it is related to what I do, plus I know the people, plus at last year’s Geneva motor show I stood on a stand of one of the fuel majors demonstrating the benefits of premium fuel to anyone who would listen (we have a car with a V8 engine, one bank ran on regular fuel, the other on super fuel, concurrently. We have endoscopes in the intakes, looking at the inlet valves and the visual difference in condition is remarkable).

So, the benefits vary depending on a number of factors. The better fuel will always be cleaner, and may also offer an additional ignition timing benefit. What this means to you in terms of value for money only you can decide. Worth mentioning that branded fuels will also tend to have some additives in their regular fuel too.
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Yamaha XJ600 | Yamaha YZF600R Thundercat | KTM 990 SMT | BMW F900XR TE

[rcbikeracer]

yes, because plastic fuel tank.

[Courier265]

All that premium fuel does is burn a hole in your wallet...

To be serious, filling up with Premium fuel will not do any harm at all
and in most cases nothing noticeable performance wise. You will not
get an increase in MPG by using the good stuff but with the additives
the carbs/infectors will benefit.

[MCN]

[Copycat73]

[kramdra]

[grr666]

I put super in the Swift, super in the Spacker, super in the scoot and regular diesel in the van but run
a tank of super through before its MOT each year.

My reasons? Well it may all be in my head but -

The Swift starts better from cold using super. I've had 43.9mpg average across 7k miles of super usage, mrs grr
never takes it above 4k when she drives it, it's rarely under 4k when I do.

The Spacker, well it's more anti social exhaust wise when it's running on super, more pops, bangs and fi-yaaaaar.

The scoot doesn't get used much at all but it seems to pull a bit better using super. I've had 70 displayed two up on that.
Not bad for a 125 scoot with 25k on the clock. It's also happier to start after a typically long layup.

The van gets it just before MOT because it seems to run a little smoother on that, I also have it valeted on MOT week,
I think if it all looks and sound up together and isn't filthy for the tester it's more likely to pass.
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Currently enjoying products from Ford, Mazda and Yamaha
Ste wrote: Avatars are fine, it's signatures that need turning off.

[Courier265]

[andyscooter]

workmate reckons he has had 30 extra miles out of his tank on his wr125
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gilera runner vxr200 (chavped)
if its spelt wrong its my fat fingers and daft auto correct on my tablet

[M.C]

Can't say I noticed an increase in MPG. It made the bike more peppy but I was going for the opposite.

[Fin]

It only really makes a difference in higher compression engines or ones running too hot that are prone to pre-ignition.

Saying that I'll put some in when the pump is out of normal fuel, I'll then feel good about it and imagine all the extra additives and extra HIGH OCTANE when in reality it doesn't make a difference to driving.

[mrmistoffelee...]

Car gets Tesco Momentum 99 or Shell V Power (TFSI engine with remap seems to prefer Momentum) i generally get an extra 3-4mpg there's a slight performance increase (or maybe my head makes it up)

Bike just gets standard. might try Momentum 99 but more for the detergent side rather than anything else.

[stevo as b4]

OP does your bike have a map switch, (not a poxy riding modes switch) I mean two or more ignition maps? If not then that'll answer your question.

Mpg and engine cleanliness are very subjective and debatable too. I personally think adding stuff to fuel in the tank is better for the latter, as you can use much more concentrated doses, which is only every a one time deal really.

Once your injectors, back of your valves, and combustion chambers are clean, the additives in SUL or aftermarket additives can't clean anything further.

More mpg? Well that can only mean that your using less fuel for the same performance or are making the same performance for less throttle opening etc. If there was more midrange torque from advanced ignition mapping, the driver might be driving differently to normal and not noticing they are changing gear sooner or using less pedal travel etc.

It works the same way as some re-mapped cars get better mpg, because they can be driven less hard for the same performance, especially tuned TDI's etc.

I think engines should be built to suit the fuel your going to run, and not the other way round generally.

And ignition timing can only do so much too. If your four stroke low output motor runs 8:1 compression, then there's probably lots of scope to play with timing on the lowest grade fuels anyway.

Also bear in mind that some cars or bikes with knock sensors don't work both ways. For example on my car the knock sensor will look for det and if it detected more than a specified limit then it'll retard the ignition in closed loop mode and feedback. What it won't do is keep advancing past the pre programmed look up tables until det occurs, like some modern car ECU's will.

That's why some modern high compression and forced induction motors can make different power levels on different fuels.

Oh and with Japanese market import cars from the 90's alot of the Japanese domestic performance models had ECU's mapped at the factory to run the 100/102RON they have available there. Less power on 95 or even on 98RON in the UK is inevitable at best, and can destroy things spectacularly at worst.

[Courier265]

[fireyphoenix1...]

I run premium fuels for a few reasons.

1, i ride a dorsoduro. Even 5% ethanol could warp my tank in short order.I do everything i can to avoid it and its only an extra 30p a tank..

2 i get an extra 11 miles from a tank. Dont sound like much ? My bikes lucky to get 90 miles between fuel stops so to me its an extra 10 mins riding before i need to find a petrol station.

3 My local station just replaced the tank they store premium in. Given the normal tank has been there a few decades i would bet there is all sorts of shit in any fuel stored in it.
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2014 Aprillia dorsoduro 750 factory.

[Powderhead]

[ThatDippyTwat]

[Powderhead]

[Hong Kong Phooey]

My tuned car runs almost twice the bhp and torque it left the factory with, it can run on unleaded, but shell v-power/nitro whatever it's called these days gives noticeable performance increase due to higher boost pressures available before knock.

It can be further enhanced by adding toluene or xylene, or even paint thinners to the fuel mix, some owners have tested 10% ratio. The ECU adjusts timing and boost fairly quickly to take full advantage.

On the carbed bike, standard fuel seems exactly the same as premium, therefore the cheapest fuel available goes in.
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'81 CG125, '97 FZS600 : '99 CBR600F4, '09 KTM RC8

[stevo as b4]

What car and engine is it, and does it run a factory ECU or an aftermarket one? My system like some Toyota and Other Japanese manufacturers ECU's is locked and unmappable and the knock sensor won't allow the ECU to start advancing on good fuel to look for knock.

[ThatDippyTwat]

[Powderhead]

[Hong Kong Phooey]

[Nobby the Bastard]

I've never taken my crash helmet off to buy petrol. I normally buy it in Sainsburys in Bristol
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
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