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you want it to go fast, dont you? :redflip
 

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There's a gun in my truck
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if i remember right, most bike say at least 92 octane and above....;)
 

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High compression ratios require a higher octane gas. You could run lower, but the engine will ping like hell. Not a good idea.
 

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CF Security Administrator,
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Only way to know for certain is look at the manual (or the sticker on the gas tank if it's still there)

Some bikes only require 89+ some need premium. Put in what the manual calls for. In some cases higher octane than is required will make the bike run worse. My '02 doesn't call for premium so I use a good quality low octane fuel...
 

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Use the lowest octane number rated for your bike.

Running too high an octane will retard performance.

The higher compression = the higher the octane needed

nm8
 

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how does putting more octane than is necessary in there hurt performance?

FI just not set up for it?
 

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Rule #34
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I doubt it needs 92 octane. That's probably the RON (research octane number)

That is NOT the octane requirement. Animator is dead right about running the lowest octane you can. High compression does not mean a high octane when you are speaking of small bore engines. 599ccs is small.

If you want to bone up..read this. It will explain something that could very well keep you fom throwing your money away.



http://www.ibmwr.org/otech/octane.html
 

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Rule #34
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Octane slow the burn. It makes the gas less burn off later. If your gas burns off too late you will not get the full power stroke of fuel burning correctly. (92 octane will prob not do this. very high octane fuel will)
 

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Scot said:
High compression does not mean a high octane when you are speaking of small bore engines. 599ccs is small.[/url]
I didnt know that. Good to know though...

I just thought it was:
The higher compression = the higher the octane needed

When in reality you are saying:
If its a bigger bore engine and it has higher compression = the higher the octane needed

cool...

learn sumthin new everyday

nm8
 

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IIRC, higher octane fuel burns faster and at a higher temperature. I've been told many times to keep it to the lowest octane your owner's manual recommends.
 

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H2O_Goalie said:
IIRC, higher octane fuel burns faster and at a higher temperature. I've been told many times to keep it to the lowest octane your owner's manual recommends.
Wait, I thought higher octane fuel burned slower- UNLESS higher compression was in place.

nm8
 

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Octane rating measures the resistance to auto-ignition (detonation) away from the flame front. Higher octane has greater resistance to detonation, which is knock.
 

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well..

If you don't want to just go by what the manual says, just do this
Try a tank of each and see how it runs, take a few notes after
riding. A good rule would be to run the lowest octane gas you
can without your engine pinging.
 

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what the hell does the size of the bore have to do with this? :confused...


50 psi in a 80ci tank is the same as 50psi in a 120ci tank, theres just more volume....



this is confusing...


I was always told that the higher the compression ratio, the higher the octane needed to prevent early detonation...

I dun see what the size of the engine has to do with this...
 

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ziadel said:
what the hell does the size of the bore have to do with this? :confused...


50 psi in a 80ci tank is the same as 50psi in a 120ci tank, theres just more volume....



this is confusing...


I was always told that the higher the compression ratio, the higher the octane needed to prevent early detonation...

I dun see what the size of the engine has to do with this...
Size has nothing to do with it. Bore does. Overall engine size is factored with both bore and stroke.

Large bore engines tend to have a higher octane requirement then smaller bore engines given the same compression ratio, because of the longer distance the flame front has to travel and the additional time available for pre-flame reactions to take place. It is possible to use two spark plugs per cylinder to lower your engine's octane needs in large bore engines. Adding a second spark plug shortens the fuel burn time and decreases the distance the flame front needs to travel.
KInda like the Honda Sabre 1100. higher compression but twin plug. NOw you know why :)
 

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I have been building engines and racing motorcycles for over 30 years. The absolutely quickest way to totally destroy a motor is detonation.Detonation is not a single event,everything affects it. Lean mixture,excessive heat,climbing a hill compared to level road riding,everything. The limit to performance is detonation. The internal effect of detonation is exactly the same as laying a piston or ring on the bench and hitting it with a hammer.The difference in cost of filling up a bike is less than $.50.I do not care if it is a modern high compression sportbike or my lawn mower,I have NEVER seen a motor "run better" on regular.The oil companies can make more low octane stuff from a barrel of oil than the "high" octane,so they "convince" you it is fine. Years ago when lead was in use,90 octane was regular,and over 100 octane could be bought at the budget stations. Since I live in Ohio,there are still race fuel outlets that supply Cam-2 standard leaded gas. The density is near pump unleaded and the single largest performance gain is to add some to the tank. The jetting will remain the same regardless of the amount added. If you want to destroy your motor just burn kerosene in it because the swill we can get now is fairly close to the same thing.
 

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I tried running regular in my R6 and it pinged like crazy so the lowest I run in it now is 92.
No more ping.
 
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