Gas

Anyone ever use racing fuel?

There is a Speedway (the gas station) about 45 minutes away that has racing fuel @ the pump...

Was thinking about picking up 2 gallons and giving her a try... hehe

 

Racing fuel will burn alot hotter due to the higher calorific value of the fuel. Is your engine old and if so it may not be up to the challenge. Heard that it is hard on the valves and prone to burning them up. Also it will also raise the combustion pressure inside your cylinders and may be hard on your gaskets and also your bearings as the connecting rod will be pushing harder on the crank. I personally have never used racing fuel in a bike so I don't know what will happen. It might be fine but I would be wary.

Mike

 

I'm not what is different between racing fuel and standard pump gas.

IF it were simply the octane was increased then it'll do next to nothing for you... octane is a flame surpressant... it would only be nessisary on your bike if you had a much higher than stock compression ratio.

I'm not sure what else is different about it - I know that it's not top fuel... that isn't even pure gas... that's mixed with an alchol (something like 85%?)

woot.

 

Dunno...

But on Saturday Im going to head out that way and pick up 2 gallons of it.

Im first going to mix 50% with normal gas and see if I can tell a difference...

Then maybe just top off with it if I can

Last I seen it was $3.50/gallon and thats before gas went to $3/gal...

8) Might be like $5 gal now...hehe

 

Oh ya forgot...

My dads friend got some "Rocket Fuel"

I need to get the low down on exactly what this stuff is, like if tis really rocket fuel, airplane fuel or what...

Anyhow whatever it is has some nitro in it. THey are adding it every now and then to their muscle cars to help boost performance...

 

Rocket fuel ?
I believe Aviation gas is cose to race gas, jet fuel is close to kerosene...

Rocket fuel is normaly oxygen + hyrdrogen etc, or hydrogen peroxide type fuels ;p

of course that is if they mean it litterally

 

I bet its aviation gas... THe friend is a pilot...

hmmm...hehe...

Whatever it is, it has some amount of Nitro in it...

 

How did this go?

 

Just FYI, avgas it most commonly 100 octane w/ lead (we call it 100 Low Lead). There are other grades, but that's the most common. I'm not sure what you could hope to get from burning it in your bike.

 

High octane fuels are slow burning mixes .. to preclude pre-ignition/detonation in highly advanced timing and or compression engines. these will do NOTHING advantageous in an engine not set up for it.
In actual fact these have significantly less energy that plain old low octane mixes... just to confuse further But this is not news.. solid information is as close as a few well placed 'clicks'.
Just the word Race gets 'em excited obviously.

 

I think you'd be better off dumping a half can of seafoam in the tank if you're having running problems or just want to "clean the system" a bit. I've had buddies run their bikes with racing fuel every once and awhile and they do claim better performance, but they also say their bikes run hot as hell with the stuff. Stick to the seafoam or some fuel injector cleaner, better safe than sorry.

 

Race gas does indeed burn slower than low octane fuels. So long as you are not pinging, race gas will be a waste of money. You will actually go slower on race gas. Personally, I love the smell of race gas. I've got to build an engine with 14:1 CR sometime, if only to please my senses.

Nachoman

 

My xj550 calls for Regular Leaded Gasoline with a min octane rating of 91, wouldnt 100LL avgas be the optimal thing to run in it ? I have just been running Mobil Super (93 octane) in it since I got it, and adding either Lucas Fuel Additive or Lead Substitute to counter the effects of the unleaded reformulated gas we now have. Any comments or suggestions would be appreciated.

 

HI Guys,

I own an '82 750XJ Maxim with 20K miles

Run Sunoco super/premium/high octane whatever... and the bike runs great....gas mileage is 40something...much better than my 4WD pick-em-up...

Debating about the pipe change - really hate the stock mufflers...turnouts are so great...then paint job & cleanup

Talked to a few folks about chopping the bike...economically unfeasible unless you REALLY want it...made sense... so I fiill it with gas & oil - then enjoy it...fun bile to ride.

Peace,

PY

 

With a vehicle nearly as old as I am (yeah, i'm only 26....) I'm hesitant to run anything other then regular unleaded.

I've been warned about the risk of running higher octane on older engines that have never run anything BUT regular unleaded.

Is this something to actually worry about ?

 

I doubt it. Your compression ratio and spark timing should dictate the fuel octane rating you use. I've come to understand that you should be able to run 87 up to about 10 to 1 compression (this is also dependent upon your spark timing so this is just a generality), which our little tickers are close to or at. If you notice "pinging" or predetonation when you are under a load (carrying more than yourself or accelerating up a hill of reasonable to stupid grade) you may want to bump it up to the next higher grade of fuel. I do not see any way that damage can result from using a lower octane in a machine regularly run on higher octane unless the machine was specifically designed to run the higher number. If you are at 10:1 or lower, try the lower octane, you probably don't need the high test.

 

Next time I fill up I'll drop a gallon of the premium stuff in there and see how she takes it.

 

What about the Leaded part, since the tag calls for Regular Leaded Gasoline with a minimum octane rating of 91 ?

 

Lead additive I'd suppose.

Stuff runs 3-4$ a small bottle around here....haneously cost inefficent for a car I think, probably ok on a bike though.

 

Thats why I was thinkin the 100LL Av gas, or even 80/87 Av gas, gives you the lead and the octane, just costs twice as much

 

As memory serves, there was another thread on just this topic a while back, don't remember the name and am too dense to figure out how to search for it (Nick, you just gotta show me how that works again, I'm hopelessly lost on that). I spend $400 having the heads in my GTO machined to accept hardened valve seats to deal with the lead loss.

 

These might be helpful.

http://www.xjbikes.com/Forums/viewtopic ... d+Gas.html

http://www.xjbikes.com/Forums/viewtopic ... d+Gas.html

If these dont work just search "Lead and Gas" in the forum search.

First one is what octane?

Second one is Octane revisited

 

Thanks Maps! Welcome, seems your earning your keep right out the gate!