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Reg. gas for an RT?

Wethead

New member
On P. 181 of my owners manual (2018 RT) it says something about reprogramming the computer to accept 87 AKI fuel.

What da heck is AKI...is that for the USA.

I been putting 92 but apparently it says 89 on my Manual.

What? I am utterly confused on this one
 
Anti-Knock Index (AKI) or (R+M)/2Edit
In most countries, including Australia, New Zealand and all of those in Europe,[citation needed] the "headline" octane rating shown on the pump is the RON, but in Canada, the United States, Brazil, and some other countries, the headline number is the average of the RON and the MON, called the Anti-Knock Index (AKI), and often written on pumps as (R+M)/2. It may also sometimes be called the Posted Octane Number (PON).
 
Your bike should be the same as my 2015 GSA, insofar as recommended fuel grade, and it is indeed 89 for the wetheads. For the adventurous types, riding around the world etc., they can have their bikes re-programmed by the dealer to run on 87.
 
Unless you're redlining your bike, you can run 87 and the bike will run fine. There is a whole debate on ADVrider about this too.
I suggest you fill the bike with what makes you happy but personally I have never had an issue with any bike running 87 but I am also not dogging the engine.
Also I do get non-ethanol gas from time to time to flush the fuel system from the corn syrup..:stick YMMV
 
Unless you're redlining your bike, you can run 87 and the bike will run fine. There is a whole debate on ADVrider about this too.
I suggest you fill the bike with what makes you happy but personally I have never had an issue with any bike running 87 but I am also not dogging the engine.
Also I do get non-ethanol gas from time to time to flush the fuel system from the corn syrup..:stick YMMV

Redlining the bike wouldn't be as much of a problem as lugging the engine and/or placing a high load on the engine at low RPM.. IMO these are the situations where detonation and damage are most likely to occur.
 
Redlining the bike wouldn't be as much of a problem as lugging the engine and/or placing a high load on the engine at low RPM.. IMO these are the situations where detonation and damage are most likely to occur.

Yes lugging the engine is another bad one for pre detonation...
 
My manual says 87 Octane. That's mid-grade around here. I've always used premium...this is my 4th RT. LC engines are different. I tried a tank if mid-grade in it. No difference in performance or sound that I can detect. Haven't checked mpg, but I imagine its very close to the same.

Only reason to use regular and get the re-programming is if you're going to places where regular is the only choice...for a long time.

Knock sensors will keep the engine from destroying itself...but you don't want to run that way for long.

Mexican gasoline is murder on fuel injection. Use a fuel injection cleaner in every other tank if you go down there.

:beer
 
There is NO knock sensor on a wethead motor.

This I did not know. Pretty amazing given octane sensing technology has been around an awfully long time on cars, but then so has variable valve timing, which some believe the mothership is going to introduce to the wethead boxer one day. Do we need it? I dunno'. I suspect Euro rules re: emissions and mpg will be the driving force, here.
 
Interesting in Iowa there was a tremendous amount of non ethanol fuel available. A lot of stations had a 89 and a 89 ethanol free. A lot had 91 ethanol free.

In Iowa 87 and 91 AKI ethanol free is common, but 89 almost always has ethanol in it.
When I fill up in Iowa I fill up with 91 ethanol free because I don't like the bikes sitting for long periods with ethanol in the tank.
We don't ride much locally so it's not unusual for the bikes to sit for a month in between rides and 5 months during winter.
In our area 87 ethanol free costs 30 cents more than 87 E10, and 91 ethanol free costs 60 cents more than 87 E10.

On trips unless the pump is clearly marked ethanol free, we use 89.
 
In Iowa 87 and 91 AKI ethanol free is common, but 89 almost always has ethanol in it.
When I fill up in Iowa I fill up with 91 ethanol free because I don't like the bikes sitting for long periods with ethanol in the tank.
We don't ride much locally so it's not unusual for the bikes to sit for a month in between rides and 5 months during winter.
In our area 87 ethanol free costs 30 cents more than 87 E10, and 91 ethanol free costs 60 cents more than 87 E10.

On trips unless the pump is clearly marked ethanol free, we use 89.

Isn't it amazing that by leaving out the corn syrup, they get to charge more....:banghead
I make it a point to get non ethanol as much as possible, the bike, boat and car run so much better and get better fuel economy to boot.YMMV
 
I use premium.

That's what I use.

I noticed a lot of stations in the Midwest, Casey's in particular, called 87 "Premium." I don't know how they get away with that. I only put a gallon of that stuff in the bike to make it to a BP station with a full spectrum of grades.
 
I always use the highest octane I can find because I ride the bike like I stole it.

The incremental cost over 89 octane is minimal and next to all of the other costs (like wearing out my tires) the extra dollar a tank full or whatever is nothing.
 
I noticed a lot of stations in the Midwest, Casey's in particular, called 87 "Premium." I don't know how they get away with that.

Casey's calls 87 without ethanol "Unleaded" and 87 with ethanol is "Super Unleaded"

Different companies in different parts of the country use different names for their gas.
They can name it anything they want. Super Unleaded, Super Duper Unleaded, Premium, ect.
When traveling in different states I never pay attention to the marketing name of the gas, I only look at the AKI name on the pump.


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Mexican gasoline is murder on fuel injection. Use a fuel injection cleaner in every other tank if you go down there.
:beer
Do you have any evidence for the claim about Mexican gas? I live in Mexico and have maybe 25,000 km on my R12R using Mexican gas. I have never added anything to the gas nor have any of my car driving friends. Mexican gas has a posted rating of 92 and they do not use ethanol. I find I get about 50 mpg in Mexico, compared to 45 mpg in the US. But the driving conditions are different so I don't claim the difference is due to the gas.
 
Isn't it amazing that by leaving out the corn syrup, they get to charge more....:banghead
I make it a point to get non ethanol as much as possible, the bike, boat and car run so much better and get better fuel economy to boot.YMMV
IMHO they need to depress the market for E0 because there's federal legislation mandating a certain amount of ethanol gets used per year, and the quota keeps going up - it amounts to a subsidy, by mandating a certain level of consumption and thus a market for it. That's part of the drive to make E15 available - it's one way to use more ethanol. The downside is many motorcycle engines won't tolerate E15, and using it will void the warranty. That debate is raging in certain quarters of the internet.

Of course as vehicle fuel economy goes up, gas (including corn gas) usage goes down, making the ethanol oversupply situation worse. Much like how fuel taxes are inadequate to maintain the roads because miles traveled (wear) has gone up faster than fuel consumption.
 
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