Buying hitest gas

[ai4px]

I just thought of something... when you go to the gas station and the pumps have one hose, have you thought about how much fuel is in the hose? Lets say you want to buy 92 octane but the guy ahead of you bought 87 octane. The last of his 87 gas is in the hose. When you pump, it's the first gas you get.

If a hose is 3/4" in diameter and is 12foot long (hose and piping inside the pump), that's about 1/4 of a gallon of 87 octane gas you get. In a car this might not make much difference, but when you are buying 2 gallons of gas, it sure would seem to. 12% of the fuel you paid for is not 92 octane.

Anyone else think of this? Anyone already thought of this and buy 92 octane at the 3 hose pumps instead?

[FrugalNinja250]

I never really thought about it since everything I buy runs fine on 87 octane. Higher octane will have zero benefit on a motor designed to run lower octane fuels, and in fact will theoretically reduce fuel combustion efficiency and thus lower gas mileage.

[Skid]

http://online.wsj.com/article/SB122944043385810527.html

This article explains it. You're getting 1/3 gallon of gas of whatever grade the previous user pumped.

[Skid]

Originally Posted by FrugalNinja250

I never really thought about it since everything I buy runs fine on 87 octane. Higher octane will have zero benefit on a motor designed to run lower octane fuels, and in fact will theoretically reduce fuel combustion efficiency and thus lower gas mileage.

Higher octane fuel just burns a bit slower. For highly-tuned cars it's required, but not necessary on a 250.

[Scattcatt]

Yep, was brought to my attention by my MSF instructor long ago, good knowledge to share for those of us who have bikes requiring higher octane ratings. I'll never use a gas station with one pump with a premium-gas-only bike

[alex.s]

Originally Posted by Skid

Higher octane fuel just burns a bit slower. For highly-tuned cars it's required, but not necessary on a 250.

it doesnt burn slower. it is harder to ignite under pressure. burns exactly the same otherwise. according to some it actually does have negative effects of increased residue so if you dont need it because you run high compression, (ninja == low compression) then dont run it.

[Jiggles]

Solution: Don't go to scrub gas stations

[austexjg]

I never thought about that in regards to the small amount of gas I usually put in - which is about a gallon. Where do they still have pumps that aren't the "Select Grade" type?

[Scattcatt]

Originally Posted by austexjg

I never thought about that in regards to the small amount of gas I usually put in - which is about a gallon. Where do they still have pumps that aren't the "Select Grade" type?

It's not so much that they aren't "select grade" type stations, it's just they have a separate hose for each grade. Like this:

[broilmebk]

Huh. I never really thought about this. With the 250 it doesn't matter much, but my car requires premium. I guess i'll have to find a three hose gas station or get in line behind another high performance car

[CZroe]

Originally Posted by broilmebk

Huh. I never really thought about this. With the 250 it doesn't matter much, but my car requires premium. I guess i'll have to find a three hose gas station or get in line behind another high performance car

It obviously doesn't matter when you're adding it to such a large tank or those pumps never would have been made.

[broilmebk]

Ahhh. Good point

[Alex]

Originally Posted by austexjg

I never thought about that in regards to the small amount of gas I usually put in - which is about a gallon. Where do they still have pumps that aren't the "Select Grade" type?

Almost nowhere in my neck of the woods. Virtually all stations have the shared hose type. Some of our bikes and cars require premium, but it's just not that big a concern, unless you're only pumping 1/2 gallon at a time.

Even if I'm only putting 3 gallons into my 10R, and worst case the prior customer was using 87 instead of the 91 I need, the math works out to:

1/3 gallon * 87 + 2 & 2/3 gallons * 91 = an effective octane rating of 90.55. Which the bike will happily run on, with zero issues. There's a larger degradation in octane rating for fuels that sit in our tanks for a few weeks, so if anything, worry about that more than the "shared hose" issue.

[alex.s]

Originally Posted by Alex

the "shared hose" issue.

i always thought thats what condoms were for

[Alex]

I thought it was if you shared condoms, you're hosed?

[alex.s]

note-to-self: only reuse your own condoms.

[menikmati]

Originally Posted by alex.s

note-to-self: only reuse your own condoms.

Needs a sticky.

[JustRidin]

Can't say I've thought of this before, but I'd say negligible in almost all cases.

[Jiggles]

Originally Posted by Alex

Almost nowhere in my neck of the woods. Virtually all stations have the shared hose type.

Really? I think I have only filled up at a shared hose station 2 or 3 times in my entire life

Disclaimer: 99% of the time I fill up at the same station less than 1 mile from where I live

[Alex]

Seriously? All of the Shells, all of the Chevrons, all of the 76's, all seem to have the new shared style. I think it was the way to go when they all had to retrofit a few years ago to put those emissions-compliant nozzles on. Where are you seeing the separate hoses? I'm going to pay more attention now and see if there are any of the other type nearby.

[Jiggles]

It could be a San Jose thing, who knows. Here what I've noticed is that the discount/cheap gas stations have shared while the more recognized brands like Chevron Shell and 76 have 3 hoses

Most of the time I make a point to fill up at Chevron because I'm weird like that

[Alex]

Originally Posted by Jiggles

Most of the time I make a point to fill up at Chevron because I'm weird like that

Our retirement accounts thank you. (wifey works for Chevron).

[Jiggles]

I'm glad my $12/week is going to a good home