Fuel octane recommendation.

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slyman

Guest
When I picked up my 2006 DR-Z400S from the dealer, the service manager told me to use mid-grade (89 octane) gasoline. The owners’ manual says I can run regular (87 octane). Even the sales brochure says 87 octane is OK due to the lower compression ratio than the E model.
My question is: Should I really be using the higher octane fuel just because I was told to or should I go with the manufacturers recommendation?
 
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tashunka

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I 2nd the motion....... I've been running supreme in my '01 KLR, mostly because the PO said it had been on supreme from day1 and recommended I do the same. The manual says 87 is usually fine, but if you get 'pinging' to go with a higher grade and it even includes some algebraic looking formula to calculate the optimal octane for your engine...... How much will a few points of octane effect things either way I wonder.... as much as it will effect my wallet over the next several decades?



edit...... this is copied and pasted from Bigcee.com's KLR FAQ page....

Should I use hi-octane fuel?
Only if your engine pings under load. High-octane gasoline does not contain any more energy than low-octane, and is intended to reduce the possibility of pre-ignition and detonation, which can be a problem with high-compression engines. An engine can gain nothing from higher octane gasoline if it is not designed to take advantage of it. That being said, any change that increases the peak compression pressure (i.e., increasing the charge of air) can cause pinging, requiring higher octane gasoline. These changes include opening up the intake path, increasing valve size, intake cam duration, etc. However, these changes are usually small, and can also be cured with jetting. Excessive carbon deposits in older engines can also increase the effective compression ratio, or provide hot spots for pre-ignition, requiring higher octane gasoline.
 

joker650

Active member
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If I am going to do any tight slow trails in the summer when the temp is high I use the Hi-Test. Normaly i go with the mid-grade.
 

GetFuzzy

New member
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Use what is recmmended by the manufacturer unless that results in pinging. While using a higher grade doesn't usually do anything other than lighten your wallet faster, some people have reported that longtime use (engine rated for regular) results in having to use high octane because of the increased carbon deposits. If using the highest octane rating is the best then we'd all be using diesel because its octane rating is off the charts.:shock:
 

c337b

Moderator
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My experience with air-cooled aircraft engines. Back in the 80's there were two fuels 80/87 octanefor engines 150HP and less and130 octane for 150HP+ engines. With the decrease in piston enginesincommercial aircraftthe oil companies eliminated both these fuels and came up will 100 octane. My 100Hpand many other low hp enginesended up burning out valves My 210HP engine had no problems.

I run 87 in 2007 DRZ400S

Frank
 
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Shawndude

Guest
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Octane does one thing, and one thing only.....stops your engine from knocking.

Run the lowest octane you can without audible knock or ping. If it knocks, you need higher octane grade.

High outside temperatures and heavy loads call for higher octane.

Higher altitudes, colder weather, lower loads (highway) lower octane.

I run 87 if cruising on the highway, 94 when beating the shit out of it in the tight stuff. It will knock when pushed hard and long enough on 87 octane, not at all if you take it easy.
 

Bayner

New member
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There are other benefits of higher octane fuels to consider as well. Many of them contain a larger dose of cleaning agents and other additives that help to keep performance at it's maximum over the long run, ie: stopping excessive carbon buildup among others. As a mechanic,I have to say as long as you're not pinging badly, as has already been stated, go ahead and use the lower octane fuels. If you know you're gonna run it hard, go with the top grades.I have seen long term benefits, especially in automobiles, from running high-end fuels.
 

Jeckyll

Member
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You run what the manual says unless you have problems.

Octane retards ignition. Period. Running octane significantly too high will not make your bike run better.

My KLR gets 87.

My 9R Ninja gets 89 octane.

My tuned turbo car gets 91 or 94, depending on which program I run, i.e. how much the timing is advanced based on the boost that's being run.

:)
 
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dane650

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well we are running hoter running engines and for the barely noticable price difference in what your putting in your tank i myself rather stay as far a way from preignition as possible pinging is damaging to your engine stay with a high octane slow burn
 
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