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Questions arising from Premix Poll

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Posted by: EBOD---------------------

I noticed in the pre-mix poll that virtually everyone used pump gas with a higher octane than that spit out by premium pumps around here (So. Calif.). Most of you had 93 or higher octane ratings for your pump gas.

Premium unleaded at all of the stations around my house (and throughout my area and on the way to my riding area) is 91 octane. I don't hear any pinging, but my engine makse so much stinking noise I could be missing it. Will running 91 octane gas have any adverse effects on my bike (in terms of power or damage to the engine)?

There's one place (it's out of the way) that sells 100 and 110 octane gas (at $3.75/gal. and $6.50/gal. respectively) to guys with exotic/classic cars. Does it seem worth the time and extra money to get gas there?

What about octane boosters? I've heard that they increase octane, but that they somehow degrade throttle response (why this is so is way beyond me). Which, if any, boosters should I consider?

Thanks for any thoughts



Posted by: Braahp---------------------

You are good to go. Manual only calls for something like 90oct so you are safe. Like me I think most just use the higher premium fuel for extra precaution. It would probaly run better on the lower oct stuff though.



Posted by: jtorres---------------------

I agree with you , anything around 90-93 will work just fine, when you use high octane fuels you are wasting money unless you are using high compression heads , for drag racing it's okay but for endurance racing the lower the compression the better.



Posted by: canyncarvr---------------------

What is octane good for anyway?

Well...as a measure of burn speed. Higher octane fuel burns SLOWER. Slow is not always good. Use of higher rated octane fuel than is needed isn't doing you any favors.

105+ is great for a 13:1 street rod. Not for your green machine.



Posted by: MLEACH---------------------

Read Eric Gorr's article Fuel for Thought-The Basics



Posted by: Cactus Jim---------------------

It also depends on what part of the country you're from. Higher elevations require lower octane levels. I'm around 2400 ft and all stations have 91 octane for premium. Lower elevations use higher, and higher use lower . I have no problems with 91 octane for my location.

Hope this helps....



Posted by: rvguy---------------------

People are confused about octane ratings. The higher the octane rating, the more resistance to combustion is has. It, however, does not burn slower. Hot spots in a cylinder will cause low octane fuel to detonate before the plug fires......causing pre-ignition and engine damage.



Posted by: larrk2300---------------------

pre ignition doesnt cause damage and you can hear it detonation is hard to hear and melts pistons.



Posted by: Brains---------------------

Just to put a spanner in the works.....

Over here (South Africa) we have both 95 and 97, leaded and unleaded and this is at sea level.
We all use 97 leaded with a premix at 40:1(some use 38:1)
- no problems

Mark.



Posted by: Jaybird---------------------

Brains,
Is pump octane rated with the ron/mon averaging method there?



Posted by: Brains---------------------

I have no idea.............
Let me ask around.




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