Newbie..Fuel

[crf250x_14]

Hey, I have a question about fuel. I live in Jamaica. I honestly do not like the gas out here for running in a bike. I would feel much safer if I was to import my own fuel into the country. I have done this before as I race go karts and we have brought down VP c-12 before. I am not really looking for fuel that is super high octane that will make my bike fly. I am just looking for a fuel that i can get that is much more consistent than ours. Which fuel would you reccomend. Also, I say this because I do not intend to spend a fortune on bringing in gas into the country for my dirt bike..lol. So which one is cheap, and would suit a 250X. (stock except for exhaust & airbox mod)

Thanx

[weatherman64]

High octane does not equal more power. More oxygen does. Get VP U4.

[FreeStyleMx]

I'd use 91 Octane if you can afford it. We run it in all our bikes.

[crf250x_14]

What octane is the VP U4 and who sells it the cheapest. I need it sent to Opa Locka FL. so i guess the cheapest place near there.

[weatherman64]

What octane is the VP U4 and who sells it the cheapest. I need it sent to Opa Locka FL. so i guess the cheapest place near there.

its 94. you will get NO benefits by running anything over 94. It is oxygenated so it makes more power. You can get it at a lot of MX shops, or a VP distributor. It costs anywhere from 50-80 dollars for a 5 gallon drum.

[crf250x_14]

WOW..as much as you guys make me want this U4, i really don't think i can afford it. It's more than 3 times the price of the best pump gas out here (shell v-power 91 octane). Bare in mind that i am not reeeealy looking for the power as such. Don't get me wrong, i don't mind the extra power, but just not for that price. I'm basically just looking for the cheapest 'Best quality' gas out there. One that I can purchase to be shipped. I am looking to spend the most $5 on a gallon cuz remember i gotta ship it also. Any suggestions ?

Also, AVGas is available out here. Not sure which one but i hear it's fairly cheap. Is this good for the bike ?

[FreeStyleMx]

Just use 91 octane. Lots of guys run it in their bikes.

[weatherman64]

dont run av. gas

[Roger M]

WOW..as much as you guys make me want this U4, i really don't think i can afford it. It's more than 3 times the price of the best pump gas out here (shell v-power 91 octane). Bare in mind that i am not reeeealy looking for the power as such. Don't get me wrong, i don't mind the extra power, but just not for that price. I'm basically just looking for the cheapest 'Best quality' gas out there. One that I can purchase to be shipped. I am looking to spend the most $5 on a gallon cuz remember i gotta ship it also. Any suggestions ?

Also, AVGas is available out here. Not sure which one but i hear it's fairly cheap. Is this good for the bike ?

Any of the VP race fuels are gonna cost $10/gal or more. U4 also breaks down quickly leaving a gum residue that will clog the fuel system if not drained after each use. I use VP MS109 which is unleaded, oxygenated to a lesser degree, 101 octane, and mix it at a ratio of 1 part to 2 parts pump gas. This ensures good quality fuel in the tank that burns clean--doesn't crud up the intake valves like pump gas alone will. Keep in mind that if you use oxygenated fuels richer jetting is advised to get the full power potential. I also plug my tank vent between rides to stop vaporization as much as possible.

[Halen]

I run a 92 octane out my way and I have not had a pinch of trouble. The higher octane may make the bike run a tiny bit smoother but I wouldn't be importing gas for power issues?

Look into re-jetting and opening up the air box and you'll be able to run farm gas in that baby!!!

later...

Van

[crf250x_14]

It's not for power issues, i just don't like the quality of this gas. It's not our normal fuel, we are importing it from another caribbean island due to an explosion at our fuel mixing station place. I've blown go kart engines from it before. I was just hoping I could somehow get a better quality fuel for cheap.

[crf250x_14]

So what's wrong with avgas. Alot of ppl race their go karts with it out here. What are the Pros & Cons of using it in the 250x ?

[crf250x_14]

anyone ?

[MidWest X]

Sorry I can't help you I have no idea how to get you fuel to you in Florida. Below is something I found on the internet. I run 100 octane race gas right from the pump for about 5.00 a gallon. It's only available at 1 gas station that I know of around here. Good Luck

ABOUT AVIATION FUELS - Aviation gasoline (or "av gas") is blended specifically for use in small aircraft. It's also commonly used by many high performance engine owners because of it's high stated octane rating (usually 100-110) and the relatively low price compared to racing fuel. Unfortunately this fuel is not all it appears to be. Av gas octane is rated on a different scale than gasolines intended for ground level use. What is 100 octane "av", is not necessarily 100 octane "ground level". Besides this, there is also a big chemical difference. Normal ground level race fuels are made up of gas molecules that have a "light end" and a "heavy end". The light end of the molecule ignites easily and burns quickly with a low temperature flame (as a piece of thin newspaper would burn). The heavy end of the molecule is not so easily ignited, but it burns with a much more intense heat (as an oak log would). This heavy end of the gasoline molecule is responsible for the hotter, more powerful part of the combustion process.

Small aircraft are constructed as very weight conscious vehicles. That's because their somewhat weak engines often have difficulty taking off with any extra weight. To help reduce this weight problem, av gasolines are blended with no heavy molecule end. This makes a gallon of av gas weigh substantially less than a gallon of ground level fuel. Since small plane engines turn very low rpms and produce so little power, the omission of the heavy end is not a horsepower issue. However, for high output pwc racing engines, there is defiantly a compromise in power. This, despite the fact that many pwc owners experience the desirable cooler operating temperatures that "av" gas offers. In addition, some blends of av gas will quickly separate from some oils used in premix situations. For the above reasons, we do not recommend the ongoing use of 100% av gas, and we will not prepare any "av gas" engine kits.

Despite all this bad news, running av gas (accepting the slight power loss) is usually a better choice than

burning down a high output engine on regular pump gas. In this situation, the best choice is usually a 50/50 mix of pump and av gas. That provides "some" heavy molecule ends for the engine.

[crf250x_14]

Ohh..So would it make sense to buy the avgas and mix it with 90 octane pump fuel. Or am I better off running the pump gas straight. (in 250x)

[MidWest X]

In your situation I think I would run 50/50 highest octane pump gas you can find mixed with the 100LL AV GAS. Good Luck!

[crf250x_14]

Just curious, why do you say in my situation ? And what exactly is the advantage of doing this ? Thanx

[MidWest X]

Your situation being you can't buy 100 octane racing gas reasonably there in Jamaica. My opinion is you would be better of improving the pump gas vs. running it straight for engine longivity. And according to the internet info I found for you they don't reccomend running AV GAS straight.

The advantage is your bike will run hot just as good as it does right after you warm it up , and it will be less likely to gum up quickly like pump gas can.

By the way I love Negril !

[crf250x_14]

Hey MidWestX, what do ya mean by "your bike will run hot just as good as it does right after you warm it up"? Also, what are the disadvantages that i'm gonna face. I'm really confused. I have the option of running straight 91 ocatane pump gas, or i can mix avgas with the 91 octane. Which should I do? The engine is stock but intake and exhaust are modded.

lol..oh yea, Negril is the best!

[MidWest X]

Hey MidWestX, what do ya mean by "your bike will run hot just as good as it does right after you warm it up"? Also, what are the disadvantages that i'm gonna face. I'm really confused. I have the option of running straight 91 ocatane pump gas, or i can mix avgas with the 91 octane. Which should I do? The engine is stock but intake and exhaust are modded.

lol..oh yea, Negril is the best!

Where I ride the mud is clay and it will pack up on the motor and raise temperatures in the motor. I haven't noticed it as much on my 4 stroke as I did on my 2 stroke that running High octane helps the motor to not pre-ignite and knock. I only notice this when the bike is hot - packed with mud - and I give it full throttle.

Also I've read in Dirt Rider that engine (valve life) life is increased by running high octane gas. The bike will run on the pump gas (91 octane) just more consistant on race gas. Better hot starts - better engine life - but more expensive.