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Octane Booster?

R

REBECCAV

Guest
Does anyone use octane booster on their airhead? Any data (or opinion) on results?
 
I got through college doing construction work.

Is an octane booster the petroleum equivalent of a carpenter's board stretcher?
 
Well, tongue in cheek aside, I must confess a limited knowledge here.

First, there is no such thing as a board stretcher. That is a common prank played on newbies on construction sites. So I am implying that producers of so-called "octane boosters" might be pulling the same type of trick on naive buyers.

That said, I have seen products in the auto supply houses that claim to boost octane. But I've not tried them for several other reasons.

1. The quality of gas today, with the additives already in the mix, makes an aftermarket additive suspect -- to my thinking.

2. Why pay for a pricy octane booster off the shelf, when simply changing grades of fuel at the pump can get what one needs for less $$ per gallon?

So I really can't offer a substantive answer regarding octane.

As a K rider, my gut says that if I use the grade of fuel that my bike "likes," and run an occasional fuel injector cleaner through it, that I'll get a consistent level of performance.

And I would expect the same from airheads in which the carbs are kept tuned and clean.

Beyond that ... :dunno
 
RickM said:
That said, I have seen products in the auto supply houses that claim to boost octane.

Yep, that's the stuff I'm talking about. It's been suggested to me that my bike would 'run better' if I use it - the theory being that in 1975 when my bike was made, the gas was a higher octane.

Re: tricks on newbies - I had a weird noise in my bike when I first got it and a friend told me that it was the radiator. I had to think about that for a bit.
 
Get me the left handed cable stretcher

That is the hazing tool on the last job site. We had a new guy going to three different Electrical Contractors on the same job site looking for one. When he hit the first one, they sent him to the second... etc. He spent 7 hours looking for one and all the electricians were smiling.

I was the one who sent him on the hunt in the first place :evil

On a more topical note, from word of mouth Sunoco typically has a "truer" octane rating. With where we are out in the midwest you may want to see if the fuel you are using has ethanol added.

If you go to Discount Auto Parts store, they have some additives that actually do work to help with the ethanol issue. The octane stuff I can not vouch for.

When is the snow going to stop:dunno
 
boxergrrlie

I would avoid auto store items as described. Having said that I do use a product made by a company called BG. They make something called 44K, and two other similar products I think 16K, and 8K. The name implies how often they should be used. This product doesn't boost octane, rather it cleans up the top end. This company also makes MOA (Motorcycle Oil Additive) that is recommended for airheads. These recommendations come from my mechanic who has been working on airheads for 20+ years, and a machinist. The machinist has built world record drag bikes, so he knows the inside parts of an engine better than 99.9% of the people you'll run into.
 
The quality of gas today, with the additives already in the mix, makes an aftermarket additive suspect -- to my thinking.


Today's gas is of a better quality for today's vehicles, however, airheads of the pre-1980 type are wanting for some lead in their go-juice. This is why I use 93 octane at the pump, and an occasional bottle of product from BG.
 
The term 'octane,' as used in fuel-grade parliance, is lengthy to define but suffice to say it only has to do with whether or not you get detonation (also known as knocking or pinging). Use the lowest grade, and if this occurs use the mid-grade and the problem should go away. If not, use the highest grade. There is no real advantage to using a higher grade than is necessary to prevent detonation. Of course you should also make sure the engine is in good proper tune before doing the fuel-grade test, as ignition timing might affect it.
Oil additives generally have a bad reputation. Fuel additives are another story, except for octane boosters which are intended for very high-performance (racing) engines that have rather high compression ratios and need all the detonation prevention they can get.
But for an older Airhead, a very good thing is to add a few ounces of Marvel's Mystery Oil (I swear I ain't makin' that up!) to every tankful of fuel. It will help a bit with prolonging the life of the valve seats, assuming of course that you still have the old leaded-gas seats. It will also help with top-cylinder lubrication.
 
It's been suggested to me that my bike would 'run better' if I use it - the theory being that in 1975 when my bike was made, the gas was a higher octane.


Not a lot to this suggestion--motorcycling is full of self-appointed experts.

There is not magic pill. Today's premium will be fine. Power comes from the mechanical tune of the engine and is hardly affected by the liquid burned.
 
Power comes from the mechanical tune of the engine and is hardly affected by the liquid burned.

Feeling a bit unsure here ... as I always thought power was directly linked to the quality of the fuel.

Does this mean I can run diesel, or kerosene in my engine?

;)
 
Power is derived from mechanical tune, but I would say that mechanical tune is greatly affected by the liquid burned.
 
RickM said:
Feeling a bit unsure here ... as I always thought power was directly linked to the quality of the fuel.

Does this mean I can run diesel, or kerosene in my engine?

;)

Well, you could if you had a diesel or jet engine.

But our engines are designed to run on gasoline. Octane is a measurement of resistance to pre ignition.

If your bike runs without pinging on regular pump gas, you don't need octane booster.
 
Octane Booster

Boxergurrlie,

What minimum octane rating does your bike require per your owners manual?

Are you running the correct heat range spark plugs according to BMW?

Any performance work done to your engine? Dual plugs, high compression pistons, head work, carbs been tweeked, etc?

Octane is a way of rating fuel. Besides it being a way of rating the anti-knock compound, you tend to get more detergents, other additives, and power out of the more expensive stuff.

Alcohol, as Paul Glaves said in a lecture at Nationals, "It clearly states in your owners manual not to use contaminated gas".

I run high test, keeps the fuel system clean, helps prevent carbon build up and generally has a lower cost per mile than the lesser octane ratings.

JON
97GS for sale
 
Re: Octane Booster

Dark Cloud said:
Octane is a way of rating fuel. Besides it being a way of rating the anti-knock compound, you tend to get more detergents, other additives, and power out of the more expensive stuff.

I run high test, keeps the fuel system clean, helps prevent carbon build up and generally has a lower cost per mile than the lesser octane ratings.

If you've got some information about that, I'd really like to see it. I run regular gas in my truck, but if it's in my best long term interest to run premium, I'd like to. The truck doesn't knock on regular, so that's what I use.

I looked at a couple of company's web sites, Shell, Mobil and Chevron, and none of them said anything about differences in additives in gasoline from one brand to another. They spoke of octane differences only.

FWIW, the Shell site, www.countonshell.com, had some cool information about using unleaded fuel in older engines and considerations of lead for valve seats.

Neat stuff.
 
Shoulda known there wouldn't be an easy answer here.

My manual calls for "gasoline with a minimun octane rating of 98." In general the bike runs great, but once in a while I get pinging when going uphill. I always use premium gas, and am not looking to solve any problems with an octane booster, I am just trying to treat the bike right and get the most out of her.

Also, I use a lead substitute in the gas such as several of you suggested.

Sbrick - I'm going to look into the BG product that you mentioned.
 
Although I believe a certain amount of positive Karma can be acrued by using additives and products your mechanic recomends, I doubt they are necessary.
As for lead substitute, IMHO you would be better off, financially and mechanically, installing unleaded valve seats. You would also benefit from a concurrent piston and head de-carbonization that's probably the cause of your pinging. (That is if it wasn't just bad gas)
Engines don't run cleaner, better, faster, cooler or more eficient by running higher octane fuel than they need run to avoid pinging. Anyone who tells you they do is either trying to sell you "snake oil" or trying to make themselves feel better about the "snake oil" that they bought.
As a matter of fact, after listening to a bunch of "mythbusters" on F650.com, I've found that my F runs BETTER on regular than it did on the mid-grade that I ran since new from suffering the delusion that higher octane was somehow "better" gas.
If your R is in good mechanical condition, it should run fine on premium (due to the compression ratio) gas without any octane boosting additives. You can also add a thicker cylinder base gasket to lower the compression and and it would probably run fine on regualar gas, but that WOULD cost some performance.
 
boxergrrlie said:
My manual calls for "gasoline with a minimun octane rating of 98."

Your manual is talking about "Research Octane Rating" USA pump gas is rated by (MON + RON)/2.
From :Grapevine Racing

Motor Octane Rating

The motor octane rating, referred to as MON (motor octane number), is the best rating to use when selecting fuel for your race or high compression engine. When testing MON, the fuel is heated to 300?? F and the intake air is heated to 100?? F. The test engine is a single cylinder 4 cycle engine that is run at 900 rpm. Ignition timing is varied with compression ratio. Engine load is varied during test.

Research Octane Ratin

Known as RON (research octane rating). Tested at 600 rpm with a fixed timing of 13?? BTDC. The fuel temp is not controlled at all and the intake air temp is varied with barometric pressure. This is done to covert everything to a SAE standard day, which is 60?? F, 0% Humidity, and 29.92 inches barometric pressure. The RON should not be used when selecting fuel for a race or high performance engine. The RON will always be higher than the MON.

(R+M)/2 Rating

This is what you get at the gas pumps. It is average of the RON and MON. It is ok to use this for lower compression street motors, but when you get much over 10:1, you should really pay attention to the MON. The closer the RON is to the MON, the more stable the fuel is. This can be very critical when running 7000+ rpm.

From How stuff works

The compression ratio of your engine determines the octane rating of the gas you must use in the car. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight -- that is what makes the engine "high performance." The disadvantage is that the gasoline for your engine costs more.

The name "octane" comes from the following fact: When you take crude oil and "crack" it in a refinery, you end up getting hydrocarbon chains of different lengths. These different chain lengths can then be separated from each other and blended to form different fuels. For example, you may have heard of methane, propane and butane. All three of them are hydrocarbons. Methane has just a single carbon atom. Propane has three carbon atoms chained together. Butane has four carbon atoms chained together. Pentane has five, hexane has six, heptane has seven and octane has eight carbons chained together.

It turns out that heptane handles compression very poorly. Compress it just a little and it ignites spontaneously. Octane handles compression very well -- you can compress it a lot and nothing happens. Eighty-seven-octane gasoline is gasoline that contains 87-percent octane and 13-percent heptane (or some other combination of fuels that has the same performance of the 87/13 combination of octane/heptane). It spontaneously ignites at a given compression level, and can only be used in engines that do not exceed that compression ratio.
 
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