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How Can I run 87 Octane Fuel?


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I know we are suppose to run 91 octane fuel however i have to drive 480km round trip to the nearest (and only one in my province of Labrador) gas station that sells Supreme. How can I mod the bike to run regular fuel instead? thicker head gasket? lower compression Piston? retard the timing? colder plug? what can I do??????

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I know we are suppose to run 91 octane fuel however i have to drive 480km round trip to the nearest (and only one in my province of Labrador) gas station that sells Supreme. How can I mod the bike to run regular fuel instead? thicker head gasket? lower compression Piston? retard the timing? colder plug? what can I do??????

Maybe try some additives to the gas...?

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I have run regular in my WR many times with zero problems. Thats beating the crap out of it and road rides in 5th gear. I run a YZ cam and the gray wire cut with a pipe. I love these bikes

Well with a 12.5:1 compression ratio and no detonation sensor (ala fuel injection) you're a very lucky guy. It's pretty likely there's some detonation going on but as much noise as these bikes make you may not hear it. That's not to say you can't run regular in an emergency but for normal riding I wouldn't run anything less than premium. If you want to set it up for regular you need to get the compression ratio down to something reasonable (9.0 - 9.5:1 at most). Don't know if you can get there with just a head gasket. Probably gonna take some machine work like a custom piston. Oh and be prepared for a significant drop in performance.

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Buy some Octane Supreme 130 from "battery stuff.com".

It is pure tetraethyl lead fuel additive in a bottle.

.5oz (about 15mL) per gallon (3.79L) of fuel will raise the octane 2 numbers from 87 to 89.

Using 1oz. (30mL) per gallon will raise the octane 3.5 numbers to 90.5, which should be okay. this stuff costs about $15/qt (973mL) including shipping in the US for two quarts

Is there a small airport near you ?

If so, purchase & mix AV100LL AvGas 50/50 with your 87 octane fuel and it will be 100 octane using the normal (R+M)/2 "pump octane AKI" rating system.

Mixing it 25/75 with your 87 octane fuel will give you about 93 octane fuel.

AV100LL is 100 MOTOR octane and about 112 pump octane.

Using AVgas is usually much cheaper than blending in Octane Supreme 130.

Be aware AV100LL AvGas is highly leaded and will require you checking your spark plug more often.

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I buy octane boost from Notre Dame in Goose Bay which only woks out to about an extra 15cents a liter...not much more than supreme. I mix it a little more than it suggests. It is about 7.50 a bottle and does 2 - 5 gal cans.

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also, I know your quite aways from there, but people going to and from often and if there was someone you knew making the trip probably wouldn't mind picking something this small up and dropping it off to you

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Wow, this is all news to me. I've had my '03 for almost two years now and have run 87 the whole time never knew I was supposed to run higher. No damage that I know of or pinging. Guess I'll do 91 now, I love this site.

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I know others that run 87 also without problem, maybe it has to do with the way it's driven also, im sure in a race type aplication it would detonate so bad it would damage the engine, but other then that it may be ok, barelly...... However I will continue to run 91, it's my buddy who wants to run 87,

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in australia we get fuel in most stations which is rumoured to be as high as 97 ron but its so crapy that it kills valve seats and caused problems in early titanium valve engines so I run a product called flash lube which is about $25 for 1 litre and it makes 1000litres of fuel .Its an upper cylinder lubricant that also slows the burn of the fuel and has the same effect as a higher octane rating .I have use 1 litre in my wr 400 and rebuilt the engine once .It was smick inside when i stripped it .I wiped the valve tops clean with a rag .no signs of detonation on the piston or the big end .Its also used in early cars running lpg/fuel .OH WELL im a believer .lol

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Its an upper cylinder lubricant that also slows the burn of the fuel and has the same effect as a higher octane rating
Octane number has nothing to do with the burning rate. Octane is resistance to detonation.
I know others that run 87 also without problem, maybe it has to do with the way it's driven also,
Detonation is most likely to occur at low RPM under a load, although it can happen any time under the right circumstance. Riding at high altitude reduces the octane requirement because the lower air density decreases the dynamic compression.

How octane is rated also bears on the question. There are two methods; Motor and Research. The Research method generally produces a higher number at any given level of detonation resistance. The requirement in the manual is for 95 Research octane. The same fuel rated by the Motor method would be around 86-88, and by the method used to label US gas pumps, an average of both methods, it would be 90-92.

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Didn't know that, but before I used it I had detonation, but after adding it it stopped. I was also thinking of buying 110 octane from a local dealer. What ratio would you recommend mixiing it with regular gas. 70-30?

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octane rating is the flash point.. burning speed.

No, it isn't. Nor is it ignitability, nor energy content.

Octane is the resistance of a fuel to ignition during the compression or combustion cycle from any source other than a spark or open flame. While the factors that influence detonation resistance can affect the burn rate, flash point, etc., they are NOT directly associated with a fuel's octane rating, and fuels with any given octane rating may be found with any of those other values all over the map.

Read:

https://www.thumpertalk.com/forum/showthread.php?p=2920255#post2920255

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I won't run 87 octane GARBAGE fuel in ANYTHING including my lawn mower.

I'd run my Torco leaded 110/Klotz R50 2-stroke fuel mix in my weed-eaters and riding tractor before 87 and have done so.

87 octane pump fuel is a "Forrest Gump box-o-chocolates" disaster for quality and consistency.

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Two-strokes are entirely different, and information regarding their fuel requirements has no application in a discussion of four stroke engines. The main difference is that the 3-5% engine oil content of pre-mix fuel lowers the effective detonation resistance of the mix, so that you have to start out with a higher octane rated fuel in order to get away with it. A YZ450 with a CR or 13:75 can run 91-93 octane fuel (R+M/2 method), whereas a two-stroke running at 12:1 is often lucky to get by with 100.

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