Fuel - What's the big deal

[Jeff]

So if the all knowledgable ones would please step forward.

What's the big deal in spending $5-15/gal for woobie-doobie race fuel when you have a bike that does not have significant motor modifications??

Most of the bikes out there don't even benefit from a 91-93 octane, and an 89 (mid-grade) will actually perform better!

Considering that I burn through 15-20 gal in a race weekend w/practice day, I can't currently justify the rapid draining of my wallet.  What am I missing???

[TZDeSioux]

Yeah really what is the big deal? Why waste money on the expensive fuels when you are competing at the regional level? Us twostroke geeks pretty much have to buy expensive race fuels so we don't kill our motors but why do you four stroke mofos waste good money on expensive fuels?

[sdiver68]

What are you missing?  ~2-4 HP on a 600, according to most dyno results I am privvy too (including my own).

How it was explained to me, maybe someone will correct me if I'm wrong on the reason for the power increase.  It's not the octane (but higher octance helps in built motors).  "Exotic" fuels are oxygenated, they carry some oxygen in them.  You are getting a little more O2 into your burn.  More 02 = more power.

My bike is mapped for both 93 Pump and VP U4.  I'll prolly only run the U4 at the bigger tracks. (RA, MAM, Barber?)

I'm not sure where you get that most bikes won't benefit from 91-93, or would run better on 89?  Most Sport bikes come from the factory with a 91 minimum, anything less is risking detonation.

[Jeff]

How it was explained to me, maybe someone will correct me if I'm wrong on the reason for the power increase.  It's not the octane (but higher octance helps in built motors).  "Exotic" fuels are oxygenated, they carry some oxygen in them.  You are getting a little more O2 into your burn.  More 02 = more power.

That makes sense.

I'm not sure where you get that most bikes won't benefit from 91-93, or would run better on 89?  Most Sport bikes come from the factory with a 91 minimum, anything less is risking detonation.

I'd have to go back and check, but I believe that most honda's are rated at 87-89.  People dump in 93 under the misconception that it will clean out carbs, burn better, or provide more power; when in fact if you use a higher octane than necessary, you are losing power.

All the octane does is allow for increased pressure before detonation.  So obviously you don't want to run anything so low that it causes pinging, but anything excessive is a waste.

That being the case, I never did understand why people drop $5-7/gal at the track for 106-113 octane fuel...

[OmniGLH]

What are you missing?  ~2-4 HP on a 600, according to most dyno results I am privvy too (including my own).

The only way a bike is going to make more horsepower on improved fuel is if it is TUNED for it.  If you take a stock bike and throw it on a dyno, and make more power by changing to race fuel, then your bike wasn't tuned/optimized for the pump gas in the first place.

I personally think that racing fuel is a waste of $5/gal for most of us.  My bike is 100% stock, motor-wise, down to the exhaust can, and I intend to leave it that way.  No reason to blow cash on racing fuel.

[Super Dave]

Octane is not an indicator of performance.  Yes, you need it in a TZ to prevent detonation.  But it's a race bike, so it was made to do this.  

Unleaded street gas is designed to combust to make power for a street vehicle.  It has certain characteristics that make it only last a certain time.  Really, gasoline is good for about 14 to 28 days before it begins to break down.  That can cause varnishing etc...

However, in a produciton based four stroke motorycycle, it does work pretty well.  It burns quickly, and at 14k PRM's...that's what you need.

What will a racing fuel do?  Well, that depends upon the fuel.  Your readily available fuels at race tracks and gas stations are pretty much '70's tech racing fuels.  They have higher octane numbers, low reid vapor pressure so that their volitilty doesn't go a way quickly.  They actually store pretty well.  They create octane through chemicals and lead.

Why lead?  The way many of the fuel rules are writting, you have to have lead in fuel so that it meets the specifics of the rules.  But leaded fuels do burn in a uniform manner also.  Unleaded racing fuels, along with street gas, kind of burn funny.  They can leave pockets of air and fuel mixture in the combustion chamber that cannot be burned.  

Oxygen...  That is the key...  The more you can put in, the more you can use to burn...  Then you can put in more fuel...  more fuel and air....  more power, more torque, better acceleration.  Pretty basic on that end.

Unleaded street gas has oxygenaters in it too.  But a really good race gas will make more BTU's of power on top than street gas.

So, as an example...  I worked with a team that did tractor pulls.  They used a real tractor...4 cylinder Massey using stock compression.  We ended up using Power Mist Dynol 832.  The octane is off the chart at 120 motor octane (MON), but it contained 12% oxygen.  The motor did not need the octane, but that wasn't going to be a limiting factor in making power.  The oxygen, however, makes a huge difference.

Now, the commonly available racing fuels do have problems with their old technology.  Because of their chemical make up, they do have a tendancy to burn slower than gasoline, they give off high amounts of heat, and they burn with a whole lot of debris.

For me, I sell fuel.  Started because I always used it for consistency.  Then it just came to point where, one, if I told someone about it, they had to have a place to get it, and two, I just started to know too much about it.

I found that it is easier for me to do no work to the engine and just put in a really good quality fuel.  Makes life easy.  I'll be one of the first to tell someone to spend the money on suspension...  but there does come a point where some extra consistency and acceleration do help.

91 octane unleaded has a different additive package when compared to a mid grade.  Often, a 91 will burn hotter and with more debris.

Do you have to run a fuel?  No.  Power Mist has an oxygenator that you can put in any fuel.  Yes, you can feel the difference.  One should make a jetting change because of the difference in the specific gravity after the oxygenator is added and you must compensate for the extra oxygen....

More questions?

[Super Dave]

Another way to look at it...

You can do all the work in the world, or none at all...

But what goes on inside the combustion chamber is all you're really worried about.  You can't change the air;  it does that all on its own.  The the structure of the molecules in the fuel...that's what releases power.

Cost?  It is bad, yes.  Consider this, it costs me about $0.95 to $1.45 a gallon just to get the fuel shipped to me.   Now, think about the volumes of fuel that are made for street use.  

It would be nice if good racing fuels were a bit less expensive, I agree.  And they are not necessarily a pour in product.  They should be tuned accordingly.  And that can be a big issue.  The terror of racing a motorcycle can be more than enough, now you throw in trying to understand jets, needles, ignition, etc... :D

[pmoravek]

The problem is that the stuff is like cocaine!
Once you use, you gotta have the stuff.

I'm partial to Nutec personally and I can definately tell the difference between the different fuels.

It's just a ratio between speed and wallet.
If you want your bike to have more balls, ya gotta feed it some vitamins.

[Super Dave]

I'd have to go back and check, but I believe that most honda's are rated at 87-89.  People dump in 93 under the misconception that it will clean out carbs, burn better, or provide more power; when in fact if you use a higher octane than necessary, you are losing power.

All the octane does is allow for increased pressure before detonation.  So obviously you don't want to run anything so low that it causes pinging, but anything excessive is a waste.

No, re read my post above.  

You are not loosing power.  But it does depend upon the fuel.  I've used Power Mist TO137 for a long time.  It has 120+ MON (on some scales, it is rated at 147).  It makes excellent power because of the chemical composition.  

Commonly available track fuels...  Again, like I stated above. they just are not appropriate.  The octane numbers are there, but that is not why they make poor power in our application.

[mdr14]

Well, as I see it, The exotic Race fuels, Such as VP MR 1 or Ulimate 4 make more horsepower pouring it in.
Your buddy goes and buys 5 gallons of it. All Of a sudden he is pulling you down the straight. Out of every corner, his bike leaps away.

Now you have to ask yourself, how can "I" give up an advantage like that.

Lets say for this example your a decent rider and your bike is set up well, about the same as your buddy.

The simple fact is the higher power producing fuels are an advanatage. They are legal. They can also be expensive. You have to ask yourself, can you afford not to?

[Thingy]

I was just talking to Hanson about this.  In non-techno speak (since I don't know techno), he said that It provided him with extra grunt off the corners (like his Ducati didn't give him enough).  I am sure that there were other benefits as well.

Is it worth it?  I don't know.  I probably depends on the rider.  Will it gain me any positions?  Maybe.  How fast do you want to go?

However, Iy do believe that it is the oxygenated fuels that make the difference.

[Peanut]

Ok I'm thinking of going this route this season but need to know more about the differences between race fuels; Nutec, VP, Powermist, etc.

What about availability?  Only @ the track for the most part?  Pre ordering mainly?

Dave it sounds like you have alot of knowledge on this subject, what 'ya got for me? ;)

Thanks.