If you don't use race gas, READ THIS:

[RIDER11X]

I use pump gas in my stock 400 motor, and use only 93-94 octane in it as Honda recomends. Now, the problem is, When I get gas in my quad can, I see most of the stations have gone to the single line pumps putting all grades of gas through the same line. Now I think you would get the first gallon or so of the grade of gas the last customer bought, no matter what you select. So I try to go to stations that have seperate lines for each octane rating.
Anyone else do this? Anyone even care?:confused: :D

[Pappy]

naaa the pumps dont operate that way.

i dont really care what kinda gas i put in it. i really dont think 4 octane points is gonna hurt anything.

[Chanman420q]

thats a good point, i had never thought of that before. but im sure that it be like a little dribble of the previous gas.

[RIDER11X]

Originally posted by Pappy
naaa the pumps dont operate that way.
Really?:huh Are you sure?

[Pappy]

haha yeah. way back when i was 15 i pumped gas. i used to lift up the hose to drain it after i finished pumping the customers gas. the owner asked wtf i was doin:p after a good laugh he explained that the fuel is pumped from the tank and metered. when the lever is released the fuel is shut off at the meter and the remaining gas in the hose (still under pressure from the pump) is already in the tank. a small dribble may still be left but not enought to be concerned with. the gas lines today have more sophisticated parts but the same principle

[RIDER11X]

Originally posted by Pappy
haha yeah. way back when i was 15 i pumped gas. i used to lift up the hose to drain it after i finished pumping the customers gas. the owner asked wtf i was doin:p after a good laugh he explained that the fuel is pumped from the tank and metered. when the lever is released the fuel is shut off at the meter and the remaining gas in the hose (still under pressure from the pump) is already in the tank. a small dribble may still be left but not enought to be concerned with. the gas lines today have more sophisticated parts but the same principle

Well I guess I'll save alot of gas by not needing to go out of my way to get to that old gas station to get my gas. Your explanation does make sence! Thanks Pappy!:cool:

[hondafox440]

Originally posted by Jingle
i dont really care what kinda gas i put in it. i really dont think 4 octane points is gonna hurt anything.

Thats a really good attitude regarding the life of your engine. I wonder if you have the same mentality about other things. "Eh, the linkage bearings don't NEED to be regreased" or "The top end doesn't HAVE to be replaced.."

:rolleyes:

[300 Hundy]

running a low octaine could make a slight ping noise

[RIDER11X]

Originally posted by 300 Hundy
running a low octaine could make a slight ping noise
That ping noise is not good for the valvetrain. It is called detonation.;)

[2004TRX450R]

Originally posted by RIDER11X
That ping noise is not good for the valvetrain. It is called detonation.;)

It's more not good for the piston than the valve train. If it doesn't ping then it don't matter if you are running regular unleaded or super. Once you hear it start to ping then you need to up the octane.

[JP400ex]

Originally posted by Pappy
naaa the pumps dont operate that way.

I disagree, especially if you have any type of motor work done. Maybe you should try putting 94 octane in once and make sure the tank is totally empty before doing so. I was just having jetting problems and was getting alot of sputtering and when i changed out my gas it ran much better and was alot easier to dial in the jetting. I thought the same thing and was running 87 octane, now its 94 only!!!

[JP400ex]

Damn, just noticed i hit quote on the wrong post! :o

[Aceman]

How do you expect to run 87 octane when you have a high comp. piston? It seems like a stock 400ex is lucky to be able to run 87 octane.

[crashinmatt]

if u guys r worried about octane, my question is what type of gas cans r u usin and on average how long is that gas in those cans? im askin this cuz i knew a guy that once told me, that when he was big in racing, that a plastic gas can will lose a few octane points or so in a weeks time. but i think he said it will lose only like up to 10 points or so total after a few weeks. so that means if u use a plastic gas can, and have gas sittin around for several weeks, that meansur 94 octance may be down to the mid 80's. now metal gas cans r supposed to hold the octane longer, but still gas is best used at its freshest point. this is only what ive been told for a guy that really knew what he was talkin about, but if i am wrong about this let me know.

[mustang93]

lmaf:rolleyes: thats like the one about putting a battery on the flore

[400exdad]

HaHa Pappy! When I was a kid on my '78 KE125, I use to do the same thing! Turn off the pump, tip of the hose and drain it into my tank. Prolly less than a quart, but on the ole Kawa, it was many miles of fun! :)

[Pappy]

Originally posted by mustang93
lmaf:rolleyes: thats like the one about putting a battery on the flore

lol...we have actually traced that myth back to detriot:p

[2004TRX450R]

Originally posted by mustang93
lmaf:rolleyes: thats like the one about putting a battery on the flore

Actually it is my understanding that it isn't totally a myth. Well with todays batteries it is but the batteries of back in the day I guess it was true. Something about the materials used for the cases of the batteries or something. They were telling us about it when I was in MMI.

Your fuel will loose octaine and go bad after being stored for awhile. The larger the volume of fuel in the can the longer it takes for it to go bad.

[mustang93]

that has nothing to do with the container being made of plastic:eek2:

Originally posted by hondafox440
Thats a really good attitude regarding the life of your engine. I wonder if you have the same mentality about other things. "Eh, the linkage bearings don't NEED to be regreased" or "The top end doesn't HAVE to be replaced.."

:rolleyes:

dude im just sayin mine doesnt ping on the lower octane so i see no need in wasteing the money on the higher octane when i can be just as happy with normal gas.

[crashinmatt]

Originally posted by mustang93
that has nothing to do with the container being made of plastic:eek2:

ok thanks, that is just what i was told, i guess i can put that one behind me. but like 2004trx450r said i know gas will lose octane over time. good to know its not the container.

[pnut420]

Originally posted by hondafox440
Thats a really good attitude regarding the life of your engine. I wonder if you have the same mentality about other things. "Eh, the linkage bearings don't NEED to be regreased" or "The top end doesn't HAVE to be replaced.."

:rolleyes:


:huh Preach on!

[2004TRX450R]

Originally posted by crashinmatt
ok thanks, that is just what i was told, i guess i can put that one behind me. but like 2004trx450r said i know gas will lose octane over time. good to know its not the container.

I'm not 100% sure but I think the container does have something to do with it as well.

[jonc623]

hello all im kinda new here and dont want to upset anyone but im lmao about this dose anyone know how octane works ? well if you dont here it is the higher the # the slower the fuel burns so if you use 87 you most likely will get spark knock because the fuel explodes faster than the higher octane fuels therefore you will get more power and less heat out of the higher octane fuel that is why you have to jet richer for the higher octane fuel like race gas to get more fuel in to the cylinder hope this helps someone and as far as the battery thing it was true when the battery case was made useing a asphalt based material not todays high impact plastic stuff

[2004TRX450R]

Originally posted by jonc623
hello all im kinda new here and dont want to upset anyone but im lmao about this dose anyone know how octane works ? well if you dont here it is the higher the # the slower the fuel burns so if you use 87 you most likely will get spark knock because the fuel explodes faster than the higher octane fuels therefore you will get more power and less heat out of the higher octane fuel that is why you have to jet richer for the higher octane fuel like race gas to get more fuel in to the cylinder hope this helps someone and as far as the battery thing it was true when the battery case was made useing a asphalt based material not todays high impact plastic stuff

Ya that is what I was getting at with the battery thing. I was thinking it was made of that but wasn't sure.

The higher the octane the more resistant to combustion it is. So with a higher octane fuel it will be harder to fire. So if you are running higher compression a lower octane will fire from the compression before the plug fires it. This is called detonation or preignition and is why you need to run higher octane fuel with higher compression. If it doesn't detonate or preignite then you don't need the higher octane fuel and you can actually make less power with to much octane because the fuel won't burn all the way properly. I've never heard of someone haveing to rejet just for higher octane rateing but when you start talking about race fuel you are dealing with a whole different thing. Race fuel is much more pure than pump gas and doesn't have all the additives to make it burn cleaner. It is usualy more dense as well so I belive you would need to lean out the mixture for running race fuel as you are getting a higher mass of fuel in for the same volume.

[trouble661]

a 400ex hold just a little over 2 gallons. dont be a cheapskate and but low octane in. it only cost about 50cents extra for the high octane. i think the 50cents is well spent.

[mustang]

finaly someone is making some sence:D

[2004TRX450R]

Originally posted by trouble661
a 400ex hold just a little over 2 gallons. dont be a cheapskate and but low octane in. it only cost about 50cents extra for the high octane. i think the 50cents is well spent.

I agree. I'm just getting at if you don't need race gas it is a waste of money. It's a little more than 50 cents more:D

[Flat Broke]

The guys that said the gas can loose octane in plastic jugs are right. But they probably don't know why. The fuel is somewhat photoreactive and some of the lead in high octane fuels such as VP etc starts to fall out of suspension when exposed to sunlight. It's not that the gas can was plastic, but rather that the gas itself was exposed to sunlight.

Call BS if you want, but a quick call to VP will yeild a similar explanation. I have seen indivdiuals pull their hair out at the race track because a motor starts detonating with no change in tune or Barometric readings. The bottom line was that the gas had been in a plastic jug all weekend outside the trailer and had dropped a couple octane points. Kind of an issue with a BBC that's setup on the ragged edge of survivability running 91 when the gas ends up being 89 by the time it gets into the car.

Chris

[Syrus]

Originally posted by Flat Broke
The guys that said the gas can loose octane in plastic jugs are right. But they probably don't know why. The fuel is somewhat photoreactive and some of the lead in high octane fuels such as VP etc starts to fall out of suspension when exposed to sunlight. It's not that the gas can was plastic, but rather that the gas itself was exposed to sunlight.

Call BS if you want, but a quick call to VP will yeild a similar explanation. I have seen indivdiuals pull their hair out at the race track because a motor starts detonating with no change in tune or Barometric readings. The bottom line was that the gas had been in a plastic jug all weekend outside the trailer and had dropped a couple octane points. Kind of an issue with a BBC that's setup on the ragged edge of survivability running 91 when the gas ends up being 89 by the time it gets into the car.

Chris

Hes got a very good point

so if u put it where sunlight wont get to it, it wont lose as fast or at all? could u jsut like throw a blanket over it?

[jonc623]

plastic gas cans are pourous and will lose strength in gas and also allow moisture to enter so i would not store gas for long periods of time as it will go bad

[tommydogtv]

I can solve this problem. Just go out to the local airport and buy airplane gas. Its around 105 octane and you will notice a power increase. Thats what i do.:devil:

[mustang93]

http://www.klotzlube.com/support/tech_bulletins/gas_dos_and_donts.pdf

[mustang93]

http://216.239.39.104/search?q=cache:DHAcVez5X6QJ:www.mgvr.org/keepers/fuels.html+plastic+gas+can+losing+octane&hl=en&start=1&ie=UTF-8

[mustang93]

Originally posted by mustang93
lmaf:rolleyes: thats like the one about putting a battery on the flore OOPS:o