www.oroadsports.com

[squirrelgadget]

I was told today that i shouldn't put unleaded 98 (or its equivalent) into a CBR600RR? that car engines for WRX's etc require that petrol as its high octane and they are high compression engines etc

is this right? does anyone know the technical stuff behind this?

[Freepers]

Dare I say, check the compression ratio of the CBR and then the WRX. I would expect the bike to have quite a high compression ratio......

Still haven't bought your japanese sewing machine??

[Freepers]

Stolen from Team Moto news:

http://www.teammoto.com.au/teammoto-enews-july-2010.php

Tech Tips: Fuels and Emissions
This month I’m going to talk about fuels and emissions. Petrol is a hydrocarbon, which consists mainly of hydrogen and carbon atoms. Petrol is very volatile which means it turns to a vapour very easily.

Petrol is rated by its anti knock properties which most of you know as its octane rating.e.g.91,95,and 98,which you see at the petrol bowser. The lower the octane rating, the more volatile the fuel.

Now, your engine compresses the air/fuel mixture during the compression stroke which generates a lot of heat. The more the air/fuel mixture is compressed, the more heat is generated.
If you were to use a petrol with a too low an octane rating, you run the risk of the fuel igniting inside the cylinder before it is supposed to. This is called detonation and is usually heard as a pinging noise when the motor is underload (hard acceleration, or going up a hill). This is the reason why most manufacturers will stipulate a specified octane fuel.

Most modern sports bikes run higher compression ratios, which in turn mean they generate higher combustion temperatures and therefore require the need for a higher octane fuel. Read your owners hand book for the correct fuel for your bike.
Carbon-Monoxide

Some things you need to know about the gases your motorcycle produces. We introduce nitrogen and oxygen into the motor via the atmosphere and into the airbox and we add liquid hydrocarbons which is the fuel. When these elements are combined and burnt, we get some nasties which aren’t great for our health, or environment.

The result is hydrocarbons, oxides of nitrogen and carbon monoxide. Rich fuel mixtures increase the carbon monoxide levels in the exhaust gas because there isn’t enough oxygen available for complete combustion.

Not enough fuel and too much air creates a lean mixture which can cause loss of power, overheating and engine damage. Oxides of nitrogen are created by high temperatures.

Carbon monoxide is an extremely poisonous gas and can be deadly when running your engine in a confined space because it absorbs the oxygen from the air. Never run your engine in a closed space, as enough CO (carbon monoxide) can be produced in a few minutes to cause death.
Catalytic converters which are fitted to most exhaust systems are designed to covert these deadly gases and therefore should not be tampered with.

[Wiccad]

Unfortunately 99.999% of the driving Bovi don't understand the concept of high RON fuels and their calorific values.

While in colder months it is true that regular unleaded (NOT E10 or Ethanol blends) can be used in high performance engines, in warmer weather it is highly not recommended.

Now here is the old school conundrum.

1) High RPM engines like most sports bikes, need fuels that are capable of keeping up a fast flame front in the combustion chamber thus a lower octane value = faster flame front. ( A classic problem in high strung high RPM carburettored 250cc bikes like CBR250RRR, Suzuki Bandit/Across 250, ZXR250 etc suffering plug fouling at high RPM as the fuel can't keep up with the motor)

2) High strung engines like most sports bikes, need fuels that do not easily detonate to protect their considerably less robust (compared to cars) internals from damage thus need fuels with a high octane value = higher detonation suppression.

The modern day reality with EFI, electronically controlled ignition systems and computer controlled throttles is that the bike has knock, oxygen and a bunch of other sensors so it knows what the fuel is doing during combustion and will compensate accordingly (FYI, Suzuki's secondary throttle system has been employed on the GSXR range since the KY 750 of 2000 meaning the computer has the final say as to how quickly throttle can be applied)

The reality in my own experience is that with the exception of extremely hot days and or track days/racing, 98 Ron fuels are a waste of money but are a better option than normal unleaded, as normal unleaded is risky as the bike has to retard itself to run safely. Regular unleaded is fine for a splash and dash if that's all you can get( i.e 2 litres to get you to another servo). But for normal use a 95-96 Ron fuel is ideal.

As for E10, keep it for the cage and use only as a measure of last resort desperation to get you to another servo. The plastic tanks in modern bikes do not like it at all. Nor do the EFI fuel lines.

[adgee]

Caltex 98 - try and always stay with the same fuel, so when you bike is tuned it is setup correctly and the computer is not chasing the ping sensor all the time.

I run this in everything from CBR600Rr's to 636's and HD's. Trackdays, road, hot or cold...

Only use something else if this is not available and I have no choice .

adgee

[hoffy]

shell power, or watevr it's called ..

[squirrelgadget]

ah cool thanks guys... this makes a bit more sense now..


everyone likes to have a bloody different opinion and confuse me!!!!

[fortytwo]

Moonshine.

[fObacademy]

i heard NOS was pretty good if you add 2 cans to your fuel


http://www.gixxer.com/forums/showthread.php?t=226570

PLEASE read at least up to page 3 it gets hella funny



of course for those who have seen it before...i had to bring it back...too good to pass up

[fortytwo]

Yes but that fuelling method only works if you employ Direct Exhaust Injection (DEI) too.

(remember this one?)

[Grip]

Also note that normal unleaded is being phased out. By 2011 there will be no unleaded fuel available for sale.

You either have to go with E10 fuel blends or premium unleaded.

E10 fuels are crap, you consume 10%-15% fuel on E10 compared to normal unleaded - where's the saving in that? You generate even more green house gases as you are consuming more fuel.

Bring on hydrogen fuel cell.

[Freepers]

If you've got a couple or hours to write off....there's a docco out there called "Who Killed The Electric Car".

Quite interesting....Hydrogen fuel cells are crap according to this. You get better efficiency burning coal, and charging your batteries

[fObacademy]

being on the uni motorsports team i can get into debates about the future of energy sources...

however in staying on topic...

i usuallu just stay away from the diesel...anything else is fine