Octane Booster?

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To add a 'twist' to this post, we have to consider the fact that on today's multi-dispensing pumps ー where you get regular, mid-grade and premium from the same pump ー there is a good chance that even if you choose premium, you end up getting a few litres of whatever the previous person was pumping, as there is a lot of fuel left in the hose and underground pipes. It's hard to tell just how much gas you have to pump before you actually get what you chose. Considering that motorcycles have small tanks and most people fill up way before being on empty, I'd say that we end up with a lower octane percentage per-tank than we think. UNLESS you get to a gas station and wait for someone to pump premium in their car and then use the same pump after they leave.
 
That is certainly a legitimate concern for vehicles with small tanks like ours, but just to clarify the switch from one grade of fuel to another is done inside the pump itself, not somewhere underground or at the tanks, so although it is entirely possible you are getting the previous person's 87 when you were trying to buy 91, at most you're getting a few liters of it.

If it's a serious concern there are still stations are there that have a completely different hose or pump for premium or super premium fuel so there is no hose sharing concerns. Alternately if left with no other option, pump the ultra premium if available (ie, 94 vs 91) and even after the 87 dilllution you'll still end up north of 91 which is what most vehicles that require premium call for.
 
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ago.on.2wheels said:
To add a 'twist' to this post, we have to consider the fact that on today's multi-dispensing pumps ー where you get regular, mid-grade and premium from the same pump ー there is a good chance that even if you choose premium, you end up getting a few litres of whatever the previous person was pumping, as there is a lot of fuel left in the hose and underground pipes. It's hard to tell just how much gas you have to pump before you actually get what you chose. Considering that motorcycles have small tanks and most people fill up way before being on empty, I'd say that we end up with a lower octane percentage per-tank than we think. UNLESS you get to a gas station and wait for someone to pump premium in their car and then use the same pump after they leave.
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Holy **** you just blew my mind.
I don't know what is real anymore.

Never thought of that. Id love to see a schematic of a typical gas pump or something to try and figure out exactly how much gas I need to pump into the nearest garbage can when I want premium haha

BTW, loneronin, this is why its sometimes ok to start a thread about something that has already been discussed to death. Because sometimes it leads to other discussion and then we learn things we hadnt thought of before like I just did :) Thats what a forum is
 
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@catzo I got curious and tried to Google it with no luck. I failed Google U. However I did find out that you can purchase a gas pump from Ali Express

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Joe Bass said:
@catzo I got curious and tried to Google it with no luck. I failed Google U. However I did find out that you can purchase a gas pump from Ali Express
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Damn it. I tried to google it too and the only thing I found out is that you can buy 1/25th sized models of classic gas pumps. I guess there are people that collect those...
So I guess someone will have to buy that gas pump and measure it out.

EDIT: I solved it!!!!!! So the switch is in the pump not underground like has been said, which is nice so the only thing left is the length of the hose. According to the American Petroleum Institute, the gas-pump hose typically retains about one third of a gallon of fuel.
Also, I found a comment from Shell- “The hose and dispensing nozzle are always full of fuel,” Shell says, adding that the residual volume in the hose from the last use depends on the diameter and length of the hose but is commonly about half a litre
Shell also adds: as long as the premium purchase is more than 10 litres, the total sale will be “on-spec for octane and meet the 91 AKI standard."

So dont fill up your bikes until they need at least 10L i guess!
I passed google u, kinda. Although I couldnt find an real schematic... Good enough!

The next time I see some middle aged woman filling up the hyundai with premium I will be getting in line behind her for a couple litres of discounted premium :D
 
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If you want a good octane booster buy a pail of toluene from the paint store. I use it on my Firebird on drag days at TMP. Generally you don't need octane for any production vehicle these days. The compression is not high enough and the computer will back off timing to prevent detonation once it detects knock. On a race engine the knock sensors will typically be tuned out and the compression will be boosted to as much as 17:1 running on a tank of witch's brew (toluene mixed with other octane additives). Most street applications can't handle more than 12.5:1 unless built for it, and a tune is absolutely necessary or the computer will negate all the gains by backing off timing and running rich. Octane boosters like MMA found in a variety of off the shelf products are a waste of money.
 
Roadghost said:
If you want a good octane booster buy a pail of toluene from the paint store. I use it on my Firebird on drag days at TMP. Generally you don't need octane for any production vehicle these days. The compression is not high enough and the computer will back off timing to prevent detonation once it detects knock. On a race engine the knock sensors will typically be tuned out and the compression will be boosted to as much as 17:1 running on a tank of witch's brew (toluene mixed with other octane additives). Most street applications can't handle more than 12.5:1 unless built for it, and a tune is absolutely necessary or the computer will negate all the gains by backing off timing and running rich. Octane boosters like MMA found in a variety of off the shelf products are a waste of money.
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Do you need to sign off to buy that pail?
 
catzo said:
Yes, it does, but BARELY. 12.2:1 for the fz6 and 12.4:1 for the r6.
12.2:1 is a plenty high compression ratio and normally an engine like that would use premium.

For comparison, the cbr 600rr also has a 12.2:1 compression ratio and obviously takes only premium.

Ive debated this a lot of the fz6 forums lol. I know there are lots of other factors than compression ratio, but it is too similiar to the engine in the r6. I'm pretty sure that yamaha only stated 87 to make the bike seem more affordable. Still, it seems to work fine. There are lots of owners of my bike that swear on 91 tho.
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Close in compression ratio, almost guaranteed the cams are very different. Duration, lift it all makes a big difference.

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RockerGuy said:
Do you need to sign off to buy that pail?
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No signature required. The best place to go is General Paint, or the other stores that exclusively deal with paint. Home Depot will rip you off every time. I get the 20L pails. Again, you don't need it unless you have raised the compression on your engine and tuned out the knock sensor.
 
Roadghost said:
No signature required. The best place to go is General Paint, or the other stores that exclusively deal with paint. Home Depot will rip you off every time. I get the 20L pails. Again, you don't need it unless you have raised the compression on your engine and tuned out the knock sensor.
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I've always wanted to source toluene as a 14yr old. Toluene is a component of TNT
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