petrol..

anthmac · 06-07-2006, 6:48 AM

ive been told mobil is the best petrol to use for cars.. friend of a friend who works for holden racing team. and also told optimax is too thick for two strokes and not ideal for 4 stroke fuel injected bikes. bp ultimate seems to run the quickest but i like the mobile synergex..

whats everyone else run and why..

also.. is it good to have a normal unleaded tank every 4th or 5th tank... ive heard that somewhere but doesnt seem to be logical

cheers

sheepofblue · 06-07-2006, 7:37 AM

I can think of no valid reason to run a different octane on any tank. If your manual calls for high grade run it. Otherwise save the cash and run regular grade. The higher octane is generally to prevent predetonation (OK watch out this will get the experts flaming me) and to use a higher than needed octane is of no value especially on a street bike.

ND4SPD · 06-07-2006, 8:04 AM

If it's a street bike, go with what your owner's manual recommends.

anthmac · 06-07-2006, 5:11 PM

well thanks americans for your lack of input. and of course there is a point running higher grade petrol. it burns hotter and cleaner.

abtech · 06-07-2006, 5:22 PM

Quote:

Originally Posted by anthmac

well thanks americans for your lack of input. and of course there is a point running higher grade petrol. it burns hotter and cleaner.

Higher grade usually means higher octane and it runs cooler than lower octane (it actually burns slower). The fact of the matter is that higher octane is only required if you have increased the compression beyond the stock level. Many "americans" run premium grade fuel because it is usually cleaner than the base "regular" grades as it is processed a few more steps and not subject to as much jobber "thinning" as regular unleaded is.

Your comment about running cleaner is usually true, but it certainly doesn't burn hotter.

sheepofblue · 06-07-2006, 5:39 PM

Quote:

Originally Posted by anthmac

well thanks americans for your lack of input. and of course there is a point running higher grade petrol. it burns hotter and cleaner.

is the south not part of the USA over there? Higher grade as in quality of brand will burn cleaner however that is not octane.
What Octane is

Also the brands are not the same over here so the info was generic on octane in general as many think running a higher octane in a stock engine will get them something.

anthmac · 06-07-2006, 8:15 PM

thanks for the link

'...a "high-performance engine" has a higher compression ratio and requires higher-octane fuel'

bikes are high compression and therefore require high octane fuel yeh...

so back to my original question.. what petrol does everyone in australia use and why?

abtech · 06-07-2006, 8:56 PM

Quote:

Originally Posted by anthmac

thanks for the link

'...a "high-performance engine" has a higher compression ratio and requires higher-octane fuel'

bikes are high compression and therefore require high octane fuel yeh...

so back to my original question.. what petrol does everyone in australia use and why?

OK, the manufacturers just recommend a certain octane because they're stupid and don't know anything about testing and designing their engines to run properly. Bikes are actually relatively low compression with regard to octane requirements above the design envelope and manufacturer's recommendations.

If a certain bike has 11.5 to 1 compression and it is raised to 12.5 by reducing the cylinder head volume, then it would require a higher octane fuel to maintain the antiknock characteristic of the lower octane fuel with the stock compression ratio. Adding octane to an engine that works properly with it's recommended octane will actually cause an incomplete burn due to the slower flame characteristics of the higher octane fuel. You gain nothing and may actually lose power.

Believe me, being in Australia doesn't change the laws of physics when applied to reciprocating engine operation even if your water does go down the toilet ass backwards.

CBR929RE · 06-07-2006, 9:10 PM

Quote:

Originally Posted by anthmac

ive been told mobil is the best petrol to use for cars.. friend of a friend who works for holden racing team. and also told optimax is too thick for two strokes and not ideal for 4 stroke fuel injected bikes. bp ultimate seems to run the quickest but i like the mobile synergex..

whats everyone else run and why..

also.. is it good to have a normal unleaded tank every 4th or 5th tank... ive heard that somewhere but doesnt seem to be logical

cheers

what do you mean by "normal unleaded"? you should be running unleaded fuel in any current vehicle (car or bike). correct me if I'm wrong but didn't all oil companies stop producing leaded gasoline back in the late 70s?

I agree with everyone else, run what the manual says (we've discussed that bit a few times on here). I run regular 87 in my bike and it runs great. I think the most important thing is don't buy from the cheapy guy on the corner cause he has the lowest price, you get what you pay for usually.

ichsnoo · 06-07-2006, 9:58 PM

Quote:

Originally Posted by anthmac

thanks for the link

'...a "high-performance engine" has a higher compression ratio and requires higher-octane fuel'

bikes are high compression and therefore require high octane fuel yeh...

so back to my original question.. what petrol does everyone in australia use and why?

G'day Mate,

I never run anything less than 95 ron in my 954 blade. If I can find it I use the 98 ron stuff. Never had a problem with my bike, never had a problem with past bikes with this strategy. Just stay away from the dodgy looking cheap arse petrol stations and you will be fine.

Cheers,
Dave aka ICHSNOO

abtech · 06-07-2006, 10:10 PM

Quote:

Originally Posted by ichsnoo

G'day Mate,

I never run anything less than 95 ron in my 954 blade. If I can find it I use the 98 ron stuff. Never had a problem with my bike, never had a problem with past bikes with this strategy. Just stay away from the dodgy looking cheap arse petrol stations and you will be fine.

Cheers,
Dave aka ICHSNOO

95 RON is roughly equivilent to our 89 octane Pump rating. (RON + MON /2).

anthmac · 06-08-2006, 12:27 AM

thanks for the responses. appreciate the now expected attitute from fireblade forum posters. awesome.

ichsnoo.. do you use optimax.. heard its too thick for bikes. or synergex or what.. what is ron.. you frmo syd what petrol do you use? do you use the high octanes like optimax, bp ultiamte or synergex??

so abtech are u saying running 98 octane fuel is worse or better ?

fck its hard to ask questions here. is high octane better? and for australian ppl.. which one is best and why...

seamus · 06-08-2006, 4:22 AM

If it's so damn hard, why do you keep coming back?

What's so hard to understand about 95 ron being the same as 89 octane? For christ's sake, it doesn't take a damn rocket scientist to figure it out. I spent 8 years in Europe and it only took me 6 months to see they're the same.

High octane is needed in high compression engines (~11.5:1 or higher). If you don't have an engine that specifically calls for a high octane fuel, you don't need it. It won't help it run better no matter how fast, hard, aggressive you run it.

anthmac · 06-08-2006, 4:40 AM

Quote:

Originally Posted by seamus

If it's so damn hard, why do you keep coming back?

What's so hard to understand about 95 ron being the same as 89 octane? For christ's sake, it doesn't take a damn rocket scientist to figure it out. I spent 8 years in Europe and it only took me 6 months to see they're the same.

High octane is needed in high compression engines (~11.5:1 or higher). If you don't have an engine that specifically calls for a high octane fuel, you don't need it. It won't help it run better no matter how fast, hard, aggressive you run it.

because i want to know what people in australia run and why... as i keep asking but dont get an answer to. thanks for your input though.

think im going to have to go elsewhere other then a message board where everyone knows everything and has an opinion on everything. even if they dont justify there answers..

'It won't help it run better'

WHY

does for cars and high compression.

fck it. fck this board. the ammount of times ive seen ppl flamed for saying they do a wheelie when clearly everyone who rides a sportsbike is constantly breaking the law by speeding is a joke. whats more funny is none of you seem to see this glaring hypocracy. some dude asked about why his engine cut out when he was doing a wheelie and there was about 15 replies with 0 answers. everyone just throwing there 2 cents in.

i read the sht on octane on howstuffworks and want to know whether high octane fuel is better or worse. you seem to say its no better or no worse. i find that hard to believe considering its been massively different when ive tried different fuels. especially noticable on my old 2 stroke 250. and i massively notice a difference when i ride with the different fuels on my 954 now.

so, for the 4th fcking time. what fuels do ppl in australia use and why? considering there is a difference in the fuels.. which one do you use/think is best and why?

Repeater · 06-08-2006, 5:08 AM

I'm not an asssi and i have no plane on flaming you, but you must understand one thing about americans. we are rather practical. if the japanese say 87 then why spend the extra cash on more expensive fuel. buy from stations that only use the real deal. meaning that some frachises buy from lower grade refiners.

as far as this board goes yes we have wit, we have humore, and yes if you are a squid you will be flamed.

we do not tolerat stunnas or asshats (still trying to figure ot the creater of that wonderful term). so please just be peaceful and maybe just maybe
you'll learn something.

: rotfl:

oh and squid don't be an asshat.

luvtolean · 06-08-2006, 6:11 AM

You come in here bitching that people on this board have opinions, then bitch you're not getting enough?

Quite the logic there chief.

BTW, what makes you so special down in Aus that what Americans say doesn't matter?

If you were less lazy and had done enough homework to have the first ****ing clue about fuel, you'd understand why your replies aren't any good. Your question is lazy and stupid.

Asking if one component in a complicated fuel like gasoline makes it better or not is utterly pointless. The answer is yes or no, just like you got.

Gasoline is made up of many parts, and you can't just judge it by what octane number is on the pump...or what your friend tells you about Brand X's fuel being thicker.

sheepofblue · 06-08-2006, 8:15 AM

athmac I wondered why you were negative rep given the reasonable nature of your first post

It seems you do not listen and get your back up quick. Read my post #2 and #6 and Abtech's posts again. No they do not deal with your BRAND question (my #6 even says I cannot help there) but they do answer the OTHER questions in your post (namely swapping octane on occasion). Also one of your countryman aided with info on brand. So it would seem you got all of your answer plus some good info, why are you whining?

Further here is the compression vs octane. A 1000RR in the USA using the native octane rating (different from Europe and Australia) has a recommended octane of 92 as minimum. A 929 under similar conditions does not. This is due to engine design differences. Adding higher octane to the 929 will not get you more performance and at some point may DECREASE performance as pointed out above.

Feel free to ignore all input on this topic and spend a bit more every tank while doing wheelies (<-the last was the only non-constructive input given so go ahead and whine about it)

schnogg · 06-08-2006, 9:32 AM

I can buy 105 octane leaded gas at a special pump at one of the stations here.

LUCIDDREAM57 · 06-08-2006, 9:36 AM

Quote:

Originally Posted by anthmac

'It won't help it run better'

WHY?

Hmm, ok, this is going to be redundant but i'll try too. Compressing forces generate heat (i.e. compression), heat generates fire. If your fuel ignites in the cylinder during the compression stroke, the piston would be trying to go up due to inertia while the fuel is burning/expanding pushing the piston down. This isn't the best way to extract power. So, high compression engines have
fuel designed to burn at a higher tempeture and slower, i.e. less explosive. If your engine does not require high octane don't use it. So, use mobil fuel. Thats fine. Any small difference if fuels that may have a negative impact on any given engine will take thousands and thousands of miles to manifest itself. Most bikes never see those kinds of miles. Any maint. or engine valve/injector cleaning that will need to be done is probably due to storage reasons, not fuel impurities. So, I hope that helps and makes sense to someone other than me.

abtech · 06-08-2006, 10:08 AM

Quote:

Originally Posted by anthmac

and i massively notice a difference when i ride with the different fuels on my 954 now.

and what dyno did you use to quantify this massive difference? The one you sit on?

luvtolean · 06-08-2006, 10:38 AM

Quote:

Originally Posted by LUCIDDREAM57

So, high compression engines have
fuel designed to burn at a higher tempeture and slower, i.e. less explosive.

Nope. Most high compression engines are also high RPM screamers, so they normally like fuel that burns fast. Bike engines are able to run high compression with lower octane because the distance the flame front has to travel is quite small, making it easier to burn all of the fuel in the chamber, leading to less active radicals and hotspotting, and also easier to evacuate the whole thing at higher RPMs during the exhaust stroke.

Octane has nothing to do with burn rate. Diesel is a very low octane fuel...and burns much slower than gasoline.

It has everything to do with pre-ignition. Higher octane is harder to get lit. Once it's lit, other things effect burn rate.

LUCIDDREAM57 · 06-08-2006, 11:03 AM

tushay, i stand corrected and will make the adjustment.

But, I think i'm right otherwise.