Fuel

[mcintyre_aerospace]

I dont know if this is considered a mod, but what kinds of fuel does everyone run in their bike. My brother works at the local airport, so I fill my bike with 100LL av gas, you know airplane fuel, and run it on just that. Ive heard people say not to run too high of octane fuel in these bikes for some reason, but I have no problem, and the bike seems more responsive and a little faster. Though this fuel tends to be a little expensive, does anyone put octane booster in theirs. Please share.

[Easy Rider]

Originally Posted by mcintyre_aerospace

and the bike seems more responsive and a little faster. Though this fuel tends to be a little expensive, does anyone put octane booster in theirs. Please share.

It's an illusion. I.E. It's all in your head !! :roll:

Honestly. If you know what octane means and what it does you would know why I say that.

High octane fuel burns a TINY bit slower and more evenly, preventing pre-ignition (knock) in a high compression engine.

High octane fuel does NOT have a higher energy content. If anything, it generates a tiny bit less power in an engine that doesn't need it.

[jonathan180iq]

When my dad and I raced Formula Vee, the standard fuel for everyone was aviation fuel. People swore up and down that this was the fuel to use because it made them faster. Well, running short on cash one weekend and not wanting to fork over the amazingly high cost of $3.50 per gallon (this was the summer of $0.50 gallons) we filled up the car with 93 octane unleaded and poured in a bottle of INSTEAD-O-LEAD and ran some of the fastest times we ever put on that car.

Moral of the story?

Don't believe the hype. Octane has nothing to do with stored energy?
Have you seen those bottles of OCTANE BOOSTER!!!!!!!!!! that are sold at autoparts stores? You know, the ones with the flashy colors and stuff? The makers of those products are making a killing off of people who think that their car or motorcycle is faster because of this product.

Our bike runs perfectly well on 87 octane gas, if you're in the states. I'm not familiar with other octane ratings outside of the US. If your bike isn't running correctly, it's not because of the octane level.

[mcintyre_aerospace]

Well heres a funny deal. I have complete access to the airports runway here, which is 7507' long, where i went out and did some speed tests, and heres my results. The top end of my bike going east with 10 mph tailwind, with regular 87 octane, which here is $3.10 right now, was 71 mph, then with all premium 95 octane ($3.30), was 74, And then 100LL I got it to 82, with the same tailwind, same direction, no carb or exhaust mods. Also 100LL gained about 3 seconds with 0-60. I dont know, but it seems that the 100LL runs great in my bike, as it does in my 88 Mustand GT, which runs really great, especially with the supercharger. So i dunno about anyone else, but it seems better to me.

[jonathan180iq]

Well then, keep using it. If it's free, I guess you'll be alright.

[Easy Rider]

Originally Posted by mcintyre_aerospace

Well heres a funny deal.

Yep, I agree with that part........I think it's "funny" alright. :roll:

1) Where are you located? Is it a private airport? I can't see any commercial public one letting you have unlimited access to the runway.

2) So, let's get this straight: You made a test run, drained the tank and the carb, put if different gas, made another run, .......

Somehow this seems like a lot of work to accomplish little of real value.

Sorry but I am skeptical of the whole story, especially the results. Others have reported exactly the opposite result.
Not impossible, mind you, just not too likely.....IMHO.

[jonathan180iq]

Well, I agree.

But, if it makes him happy and it doesn't cost him any extra money, then he can just keep putting it in and living in bliss.

Like I said, from personal experience, it didn't help in the racecar. I wouldn't pay for it anyway, as the slight difference in performance isn't worth the cost, if it exists at all.

[trykemike]

Just an observation but mid-grade in Toronto is 89 octane. I have a tach and when I use 89 octane I can regularly pull
7750 rpm in 5th gear and over 8000 rpm in 4 th gear ( not adviseable )

when I use 87 octane I can't max 5 th at 7500 rpm.

[mcintyre_aerospace]

Yeah the airport is county run, my bro works here, and they sump all the tanks and trucks everyday, so he saves me the otherwise thrown away fuel. The timed results are guessed, but the speed tests are right. I recently removed my gas tank to remove a dent, so i had to drain all the gas, which was regular. Beforehand i had did a lot of test runs, you know for fun, im only 20, and I have access the the runways, not a whole lot of traffic here in the west Texan desert, so i know the top speed my bike reached with regular. Then I started with the 100 LL and rode for a week or so until i had no reg gas in it, I never go to gas stations. After quizzically posting I decided to run it and, yes, it did run faster than with reg gas. I also like to go to a place called Pennwell, about 10 miles west of Odessa on I-10, where they have a drag strip. My dad friend, who has a supercharged 67 Nova, have run all kinds of fuel in the drag races, and he prefers the airports 100LL because it gains him about .7 of a second, which is a lot because it normally runs under 11s. He also told me he gains around 13 more horsepower on the dino, but i don't know about that. Maybe our 100LL is a little different, but he loves it. Either way, its still a little single cylinder bike, you cant expect a whole lot out of it. All I wanted to really know was, is it bad for the carb and or valves.

[Easy Rider]

Originally Posted by mcintyre_aerospace

Then I started with the 100 LL and rode for a week or so until i had no reg gas in it, I never go to gas stations.

, who has a supercharged 67 Nova, have run all kinds of fuel in the drag races, and he prefers the airports 100LL because it gains him about .7 of a second, Either way, its still a little single cylinder bike, you cant expect a whole lot out of it.

OK, fine. Your original story sounded like you did all the tests the same day. Since that is NOT the case, you can't be sure about the wind on those different test days and with only 250 cc, the wind can make a BIG difference........or how much you were crouched down.

In your case, it makes sense to use whatever is available on the day you need to fill up. That is NOT the case for most people. Bottom line for me is: At 60 MPG, there ain't much difference in cost regardless of what you use.........so if you THINK it runs better by going for the "premium" pump, then do it. If it makes you feel good, then do it. Just don't preach it to others as gospel.

As for the drag racer..........DUH...........no surprise that it requires high octane. It was designed that way. If he ran 87 octane, it would probably blow up on the first run.

> All I wanted to really know was, is it bad for the carb and or valves.

NO. Use whatever makes you happy. That IS the point of riding, after all.