[Niceorange]

Hi all,

Before the riding season began I unplugged my 02s based on the recommendation of so many here. What I have noticed over about 200 miles unplugged is that I am getting more backfiring on shifts, as well as occasionally on startup. I also only got 37.2 MPG on the last tank. I'm inclined to run it like this a bit longer to see what the real MPG is over a few tanks (too much variability in a single fill-up to know what it's really using), but wanted to get your opinions as to whether I should reconnect the 02s sooner. I figure the worst thing I can do is foul a set of plugs and soot up the exhaust... right?

 

[kevinx]

Depending on fuel source, and riding habits. MPG may vary greatly. The use of premium fuels in mostly stock Vics is also a cause of pops, and low MPG. Your o2 unplugged will not cause a fouled plug

 

[Niceorange]

Oh interesting... i have been running premium thinking it would perform better. Would I be better off switching to regular?

 

[kevinx]

Oh interesting... i have been running premium thinking it would perform better. Would I be better off switching to regular?

Yup....The recomended octane is for the dumbest person in the worst conditions. If it is below 95 degrees F. Then you are simply creating carbon build up with premium.

 

[Niceorange]

With the timing wheel (set at +4) I was thinking I'd help the motor running 91. I'll try running some regular and hopefully the backfiring goes away.

 

[bikendad]

With the timing wheel (set at +4) I was thinking I'd help the motor running 91. I'll try running some regular and hopefully the backfiring goes away.

NOOOOO, Kevinx was telling you to run Regular in a STOCK Vic not one with the timing bumped up!!!

 

[Daddio]

I run regular w/ the timing whell at +4, without pinging. Prolonged use of too high of octane fuel will carbon up your heads, until you must use premium...

 

[lmn2k]

i'm running regular, still cool here, but haven't noticed or heard any pinging yet. Started with 91, ran a few tanks of 89, now down to first tank at 87, well see how the rise in temp treats it, but until hear pinging or notice a significant reduction in performance/fuel economy, i'll run 87.... maybe 89...

 

[mdallen]

NOOOOO, Kevinx was telling you to run Regular in a STOCK Vic not one with the timing bumped up!!!

I'm not KevinX but running a tank of 89 to see if it stops the back firing won't hurt. If he gets any pings then he could just add some octance booster.

 

[K1ll3m@LL]

So if you have a few upgrades its better to run higher octane or lower unless you hear pinging?

 

[Blowndodge]

I've ran my 2013 unplugged on regular 87 for 25,000 miles. Not a ping in a poke! If I added a timing wheel and advanced it I might have to make changes. Sounds like some on here are realizing Premium fuel doesn't have mystical power enhancing formulas. Premium is nothing more than gas that has additives that are harder to spontaneously ignite. Stockers that are unplugged should be running regular 87...

 

[bikendad]

So if you have a few upgrades its better to run higher octane or lower unless you hear pinging?

Depends on what the "upgrades" are. Hi octane fuel is only needed in motors running high compression or advanced timing, it also helps prevent pre-ignition/pinging if you're running very lean. So if your upgrades include advanced ignition timing or say high compression pistons then yes you will want to consider using premium high octane fuel. I would not run 87 regular in a Vic using a timing gear set at+4. That dictates premium, you Might get away with 89 in Cool weather but no guarantees.

 

[K1ll3m@LL]

I have always run the high octane guess i'll just keep it that way

 

[primethious]

I ran a tank of 87 with 4 degrees and no ping. My concern is that I've read that low octane has ethanol whereas 92 does not. so for storage 92 for sure.

 

[mdallen]

I ran a tank of 87 with 4 degrees and no ping. My concern is that I've read that low octane has ethanol whereas 92 does not. so for storage 92 for sure.

This may help, Lloyd's take on ethanol and the 106 (under alcohol abuse):

Lloydz Motorworkz

 

[slej]

:attention1: Seems Llyods changed their webpage yesterday and now all the tech tip links are broken! :22yikes:

 

[recumbentbob]

I ran a tank of 87 with 4 degrees and no ping. My concern is that I've read that low octane has ethanol whereas 92 does not. so for storage 92 for sure.

Ethanol In Premium Gas?

There is a difference between states on whether premium gas specifically has ethanol in it or not. Or, more correctly, whether it's required to have it in it. Two states in the Union, Missouri and Montana, have specific exemption to allow ethanol-free premium gasoline. So if you live in one of those two states, you can be thankful.
For the rest of us, we are faced with the unpleasant reality that the refineries are all but tied into putting ethanol in premium gas. This is because they have to use the ethanol to raise the octane level of their gasoline blend in order to satisfy the higher octane requirements of premium. This is one reason why you don't get better gas mileage with premium gas, because an essential part of that blend is a component that has less energy and forces the gas mileage down simply by nature.
So don't get fooled into thinking you can escape ethanol's grasp simply by paying more and getting premium gas.

 

[Oldman47]

Yes 10% ethanol in 94 octane here in IL.

 

[miami]

now that the temp is below 95 here, i am going to run lower octane fuel and will dongle the 02 sensors for the winter riding.