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Genuine Scooter Octane Update (All Models!)
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iamryan25
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2013 Genuine Buddy 125cc (Red)

PostPosted: Tue Mar 04, 2014 12:49 am    Post subject: Genuine Scooter Octane Update (All Models!) Reply with quote

I figured it was worth sharing seeing as how it includes recommendations for the entire current and previous Genuine line-up for all engine sizes.

Here is Genuine's verbatim response to my inquiry about octane:

"Hi Ryan,

We spoke with our experts and they passed along the following breakdown:

Here are the recommended minimum octanes for our legacy and current models. These octane figures are based on the engine compression ratio and having electronic ignition with a built in advance.

Buddy 50, Roughhouse 50, Black Cat 50, and Rattler 50: regular 87 octane

Rattler 110: regular 87 octane

Buddy 125: mid 89 octane

Buddy 150 and Blur 150: mid 89 octane

Buddy 170 and Hooligan 170: high 91 or 93 octane

Blur 220: high 91 or 93 octane

Stella 150 2T: mid 89 octane

Stella 150 4T: mid 89 octane

Stella automatic: mid 89 octane

For the Buddy 125 model: although the recommended octane is 89, we have had many reports from dealers and consumers that have been running regular 87 with no issues and several thousands of miles.

Best,
Genuine Scooters"

Very Happy
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still shifting
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PostPosted: Tue Mar 04, 2014 3:14 am    Post subject: Reply with quote

Very Interesting and Helpful I for one wish other manufacturers were as forth coming. R
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BoulderBud
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PostPosted: Tue Mar 04, 2014 3:55 am    Post subject: Reply with quote

Does the 10% ethanol content have anything to do with why we shouldn't use 85 octane? And, if we can get 100% gas, should we use it?
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Dooglas
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PostPosted: Tue Mar 04, 2014 4:15 am    Post subject: Reply with quote

BoulderBud wrote:
Does the 10% ethanol content have anything to do with why we shouldn't use 85 octane? And, if we can get 100% gas, should we use it?

The recreational gas with no ethanol that is available at many stations and marine fuel docks is usually rated at 90 octane. That would seem to meet most any of the Genuine recommendations. (regular gas is usually rated at 87 octane - I'm confused by your reference to 85 octane)
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iamryan25
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PostPosted: Tue Mar 04, 2014 4:34 am    Post subject: Reply with quote

No mention of a recommendation for the genuine 300 cruiser...
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ericalm
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PostPosted: Tue Mar 04, 2014 5:07 am    Post subject: Reply with quote

Interesting! Thanks for sharing. I'm going to add to our FAQ!
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Witch
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PostPosted: Tue Mar 04, 2014 5:25 am    Post subject: Reply with quote

I always try to go for the fancy stuff when I can. But it's nice to know the minimums, regardless. Good on you for getting this info!

iamryan25 wrote:
No mention of a recommendation for the genuine 300 cruiser...


Well, obviously they're still testing it. Though I'd hazard a guess it might require unicorn tears as a recommended occasional fuel treatment.
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skully93
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PostPosted: Tue Mar 04, 2014 6:10 pm    Post subject: Reply with quote

oops!

I've been putting 85 in ours...

I can easily make the jump to 87.

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scootERIK
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PostPosted: Tue Mar 04, 2014 6:39 pm    Post subject: Reply with quote

skully93 wrote:
oops!

I've been putting 85 in ours...

I can easily make the jump to 87.


Doesn't the octane requirement change at higher elevations?
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Steve S
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PostPosted: Tue Mar 04, 2014 7:00 pm    Post subject: Reply with quote

Octane requirement is lower at high altitude.
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SockyTX
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PostPosted: Tue Mar 04, 2014 7:07 pm    Post subject: Reply with quote

Um, I've been using 87 since mile 1 about to hit 9500. So do I just start using 89?
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skully93
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PostPosted: Tue Mar 04, 2014 8:16 pm    Post subject: Reply with quote

Steve S wrote:
Octane requirement is lower at high altitude.


maybe that's it. we live at 6k feet, and routinely go to 9k.

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jrstone
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PostPosted: Tue Mar 04, 2014 10:39 pm    Post subject: Reply with quote

I called Genuine when I first got the Buddy and asked what they recommended and they said 87 was fine, so that's what I've been using. Haven't had any issues.
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PostPosted: Tue Mar 04, 2014 10:45 pm    Post subject: Reply with quote

jrstone wrote:
I called Genuine when I first got the Buddy and asked what they recommended and they said 87 was fine, so that's what I've been using. Haven't had any issues.

If it ain't broke....

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Roofaloof
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PostPosted: Tue Mar 04, 2014 11:59 pm    Post subject: Reply with quote

Interesting. I've had my 150cc Blackjack from 900-2000miles and run it on 87. Never had any issues.

I've been thinking about bumping up the compression, which would necessitate a higher octane.
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evilbean42
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PostPosted: Wed Mar 05, 2014 6:06 am    Post subject: Reply with quote

As far as I know there is no 85 octane. If you are referring to E85 that is a special blend of fuel that is 85% Ethanol instead of the standard 10%. This is for use only in vehicles with engines that are specially designed for it such as GMs "Flex Fuel" engines.

The octane rating does not refer to ethanol content, octane is a measure of how resistant a fuel is to detonation, or exploding in the combustion chamber as opposed to burning. Higher octane fuels have more additives which help them resist detonation.
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PostPosted: Wed Mar 05, 2014 6:24 am    Post subject: Reply with quote

evilbean42 wrote:
As far as I know there is no 85 octane.
According to this site (and I trust that skully knows what he is putting in his tank), skully is correct, 85 octane is 'regular' gas in Denver and the Colorado mountains.
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still shifting
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PostPosted: Wed Mar 05, 2014 1:48 pm    Post subject: Reply with quote

Also true in NM. R
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Quo Vadimus
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PostPosted: Wed Mar 05, 2014 4:09 pm    Post subject: Reply with quote

I could swear I watched a Genuine-produced youtube vid of a Buddy 50 prep at a dealer, wherein they said to use 89. I'd been using 87 prior to that.
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skully93
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PostPosted: Wed Mar 05, 2014 7:39 pm    Post subject: Reply with quote

Syd wrote:
/doc/1G1-81066292.html]this site[/url] (and I trust that skully knows what he is putting in his tank), skully is correct, 85 octane is 'regular' gas in Denver and the Colorado mountains.


Yep! we usually select from 85, 87, 91.

Been using 85 in the buddys and 87 in the hondas, so far so good?

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NeoGenesisMax
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PostPosted: Thu Mar 06, 2014 8:49 am    Post subject: Reply with quote

I always put 91 ethenol free in my buddy 50 while I had it. My cheepo chinese scooter definately idled differently with 87 octane compared to 91 or 93. And all three scooters i have/had ran better on fresh fuel.
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evilbean42
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PostPosted: Fri Mar 07, 2014 5:22 am    Post subject: Reply with quote

Wow, I guess I need to leave the east coast a little more, I had no idea other areas had adjusted octane ranges... Just out of curiosity, to anyone in an 85 octane regular area, what is your premium octane rating? That article mentioned a regular 85, and a mid of 87, but didn't get into premium. I'm just wondering if you have an additional grade that isn't available by me, or if they actually slid the the whole range down and cut off the top.[/quote]
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PostPosted: Fri Mar 07, 2014 2:47 pm    Post subject: Reply with quote

91 (and sometimes 92) is the highest we have here.
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toot
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PostPosted: Fri Mar 07, 2014 4:21 pm    Post subject: Stella Reply with quote

I actually filled my Stella for second time fill up with 89 instead if 87, it seem to run better!!! Maybe coincidence?? Just seem to climb the same ole hill better!!!! Razz Razz Razz
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PostPosted: Fri Mar 07, 2014 8:09 pm    Post subject: Re: Stella Reply with quote

toot wrote:
I actually filled my Stella for second time fill up with 89 instead if 87, it seem to run better!!! Maybe coincidence?? Just seem to climb the same ole hill better!!!! Razz Razz Razz

Yes, a coincidence.

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DaBinChe
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PostPosted: Sat Mar 08, 2014 9:09 pm    Post subject: Reply with quote

in the mount states where elevation is higher, i.e. lower air density, your compression isn't as high as sea level hence not needing as high an octane so an 85 is the same as an 87
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CountChocula
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PostPosted: Sun Mar 09, 2014 7:43 pm    Post subject: Reply with quote

Agreed. 85 octane in Colorado or other states at altitude is equivalent to 87 at sea level. I always ran premium in my modified Malossi 70cc engined Aprilia SR50 until a well known SR50 builder told me to stick with 85 (87) as there's more energy in the lower grade gas. He was right...ran with what felt like more power.

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kmrcstintn
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PostPosted: Wed Mar 19, 2014 2:50 am    Post subject: Reply with quote

good to know...now I can fuel the entire fleet (SUV, motorcycle, and scooter) with 87 octane, which will save $$$! now if I can find a local fuel station that carries Pure Gas...closest ones I know of are 20+ miles from my house Mad
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PostPosted: Wed Mar 19, 2014 4:58 am    Post subject: Reply with quote

kmrcstintn wrote:
good to know...now I can fuel the entire fleet (SUV, motorcycle, and scooter) with 87 octane, which will save $$$! now if I can find a local fuel station that carries Pure Gas...
iamryan25 wrote:
We spoke with our experts and they passed along the following breakdown: Buddy 125: mid 89 octane

Ah, seems like this thread really endorsed about 89 octane for the Buddy 125. And if you do find ethanol free gas nearby - I believe it will be about 90 octane and it won't be cheaper.
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hal888
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PostPosted: Wed Mar 19, 2014 1:26 pm    Post subject: Reply with quote

Dooglas wrote:
kmrcstintn wrote:
good to know...now I can fuel the entire fleet (SUV, motorcycle, and scooter) with 87 octane, which will save $$$! now if I can find a local fuel station that carries Pure Gas...
iamryan25 wrote:
We spoke with our experts and they passed along the following breakdown: Buddy 125: mid 89 octane

Ah, seems like this thread really endorsed about 89 octane for the Buddy 125. And if you do find ethanol free gas nearby - I believe it will be about 90 octane and it won't be cheaper.


I've always been a little concerned that gas companies that produce ethanol free gas such as Pure don't put the same additives or cleansers into the fuel. Maybe that's actually a good thing, but if the bike rides fine with a 10% ethanol mix, and the additives are helpful, and the fuel is used relatively quickly such that fuel break-down is not an issue, then is ethanol-free gas worth the cost?

(not trying to hi-jack the thread - please continue)
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PostPosted: Wed Mar 19, 2014 2:01 pm    Post subject: Reply with quote

You don't get as good of fuel economy with ethanol gas, so I don't think the savings at the pump really saves you any money in the long run.
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iamryan25
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PostPosted: Wed Mar 19, 2014 6:28 pm    Post subject: Reply with quote

Dooglas wrote:
And if you do find ethanol free gas nearby - I believe it will be about 90 octane and it won't be cheaper.

Where I live the only ethanol free available without an account/membership to a fuel station is 87. It sounds like ethanol free octanes really vary by location.
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PostPosted: Wed Mar 19, 2014 6:28 pm    Post subject: Reply with quote

thanks for the correction...yes the 'official' endorsement is for 89 octane, but several responses stated 87 octane use without noticable detrimental effects; so for legal and influential clarification...I (as in me, myself, and I) might want to try 87 octane since it seems to work in other people's scoots as they have posted in this thread; thank you

as far as the cost of PureGas vs ethanol blended gasoline...I incur extra cost with the regular use of ethanol stabilizer and fuel system cleaner to nullify the negative effects of ethanol in the gasoline, so it might not be a burden to switch over; gonna have to buy a batch and see what the monetary damage is vs E10 (soon to be E15 is the EPA has its way) & fuel system treatments...thank you

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iamryan25
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PostPosted: Wed Mar 19, 2014 6:34 pm    Post subject: Reply with quote

kmrcstintn wrote:
thanks for the correction...yes the 'official' endorsement is for 89 octane, but several responses stated 87 octane use without noticable detrimental effects; so for legal and influential clarification...I (as in me, myself, and I) might want to try 87 octane since it seems to work in other people's scoots as they have posted in this thread; thank you


With proper routine maintenance, and avoidance of "cheaper" gas offered by stations like Maverick or Stinker, your Buddy ought to last a long long time -- regardless of whether you're putting in 87 or 89.

I've been running 87 because it is difficult to find a station with a separate hose for each octane, and the length of the fuel hose could easily be a gallon... so even if I try to add mid-grade, whatever was in the hose before me (likely 87) fills my tank before the mid-grade gets to my tank.
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PostPosted: Thu Mar 20, 2014 9:45 pm    Post subject: Reply with quote

iamryan25 wrote:
With proper routine maintenance, and avoidance of "cheaper" gas offered by stations like Maverick or Stinker,

Why do you think Maverick gas is "less" than other gas? It will come from the same distribution point as any other, and every Maverick I have seen is busy as can be, so it's not like the gas sits.

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PostPosted: Wed Jul 02, 2014 3:49 pm    Post subject: Re gas requirements Reply with quote

I am the proud owner of a 2nd hand Stella 2T, 2004. The dealer said it has been run on 91 octane premium (Connecticut). Any suggestion about weaning it off the hi test? Would going straight to 87 from an empty tank cause a crisis in the carb?
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skully93
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PostPosted: Wed Jul 02, 2014 4:09 pm    Post subject: Reply with quote

I would just go for it. Worst case you can ride out the gas if you don't like it.

I use 87 in my Hondas and 85 in the buddy's seem to be just fine.

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PostPosted: Wed Jul 02, 2014 4:18 pm    Post subject: Reply with quote

40K miles on my '08.
Always run the cheapest gas (but I use Conoco exclusively).
Live in Denver so we get lots of ethanol in our gas.
Never cleaned the carb.
Scooter kicks ass.

Nuff said.

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PostPosted: Wed Jul 02, 2014 4:18 pm    Post subject: Reply with quote

I was told by the previous owner to use 0 ethanol gas. Fortunately, there is a feed store close by which has this. I didn't notice what the octane was when I filled up the other day. The difference in price per gallon is maybe 50 cents. Think about it. 50 cents won't even buy you a phone call or a cup of anything.
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PostPosted: Wed Jul 02, 2014 5:42 pm    Post subject: Reply with quote

snoozy wrote:
I was told by the previous owner to use 0 ethanol gas. Fortunately, there is a feed store close by which has this. I didn't notice what the octane was when I filled up the other day. The difference in price per gallon is maybe 50 cents. Think about it. 50 cents won't even buy you a phone call or a cup of anything.


24,300 miles on my Buddy 125 all using ~10% ethanol and I haven't had any problems.
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PostPosted: Wed Jul 02, 2014 6:47 pm    Post subject: Reply with quote

Well, of course! Let's just throw this debate into the arena with synthetic/dino/diesel/auto/moto oil and let them duke it out. Whaddya say? Laughing
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PostPosted: Wed Jul 02, 2014 9:36 pm    Post subject: Reply with quote

I run 87 E10 no problem. The only difference I noted was with 91 non-eth, but that's probably because the scooter was jetted lean stock, and non-eth requires less fuel for stoich (optimum ratio). Since swapping out the stock 90 main jet to a 92, it's run much better on E10, and actually the timing could be advanced (meaning too high of an octane fuel for the stock ignition timing).
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PostPosted: Thu Jul 03, 2014 5:41 am    Post subject: Reply with quote

As far as the Stella 2T goes: 2 cycle engines tend to be lower compression engines and therefore would not need higher octane fuel. Follow the recommendations in your user manual.
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PostPosted: Thu Jul 03, 2014 7:22 am    Post subject: Reply with quote

OldGuy wrote:
As far as the Stella 2T goes: 2 cycle engines tend to be lower compression engines and therefore would not need higher octane fuel. Follow the recommendations in your user manual.


But 2T oil is an octane rating depressant, meaning it lowers the octane rating of the fuel it's added to, especially in the quantities most 2T engines require.

But unless there's knocking, pinging or some other sign of preignition or detonation, there's no need to run higher octane fuel. You'll get the highest performance by running an octane rating just high enough to prevent preignition/detonation, and running anything higher can actually hurt performance slightly.

This all factors into the idea of ignition timing. Basically you want the flame front to be spread across the cylinder at top dead center (ATDC) and to have the fuel burn throughout the power stroke. Since it takes time for the flame front to spread after your ignition event (spark plug firing), your ignition timing usually fires the spark before top dead center (BTDC). At low RPM, the ignition is retarded to just slightly BTDC, mid RPM it's advanced to more BTDC, at high RPM it's retarded again (fuel burns faster and is more easily ignitable under high RPM/high load conditions, this is why knock/pinging generally happens then). This is on a variable ignition timing system, some small engines use fixed ignition timing. But the idea is a fuel of too high an octane rating will burn slower, allowing your engine to extract less energy from the combustion event. But if it burns too fast, it will work against your piston as it's compressing the A/F mixture, wasting energy, causing the noise known as knock/pinging, and, potentially if it's bad enough, causing physical damage.


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OldGuy
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PostPosted: Thu Jul 03, 2014 2:35 pm    Post subject: Reply with quote

You are correct about oil in fuel depressing the octane rating. And, good description too. This is why a car that burns oil also tends to knock or ping.

Still, the compression ratio of the Roughhouse and Buddy 50 is something like 6.5:1. (Not exactly sure.) And I suspect the 2T Stella is about the same. So, even with oil, 87 octane works (for me) without any problem.

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danlbob
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PostPosted: Wed Sep 17, 2014 11:28 pm    Post subject: Reply with quote

Can using higher than recommended octane gas (especially at high altitude) cause performance issues? Or is it just wasteful?
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Syd
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PostPosted: Thu Sep 18, 2014 3:15 am    Post subject: Reply with quote

danlbob wrote:
Can using higher than recommended octane gas (especially at high altitude) cause performance issues? Or is it just wasteful?

I'm no chemical engineer but I think, assuming everything is running normally, it is just wasteful.

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PostPosted: Thu Sep 18, 2014 12:06 pm    Post subject: Reply with quote

danlbob wrote:
Can using higher than recommended octane gas (especially at high altitude) cause performance issues? Or is it just wasteful?


Higher octane gas is less volatile (harder to ignite). If an engine is designed and tuned for regular gas, the harder-to-ignite premium gas can cause harder starting, rougher idling, plug fouling, and excessive carbon buildup-- pretty much the same symptoms as a too-rich fuel/gas mixture.

Using premium in a Prius can actually trip the "check engine" light, though I doubt an occasional tank in a scooter will hurt much.
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PostPosted: Sun Sep 28, 2014 9:02 pm    Post subject: Reply with quote

evilbean42 wrote:
Wow, I guess I need to leave the east coast a little more, I had no idea other areas had adjusted octane ranges... Just out of curiosity, to anyone in an 85 octane regular area, what is your premium octane rating? That article mentioned a regular 85, and a mid of 87, but didn't get into premium. I'm just wondering if you have an additional grade that isn't available by me, or if they actually slid the the whole range down and cut off the top.
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I'm originally from Washington. In Washington, the octane options at a gas station was 87, 89, 93. I would routinely travel through Montana and Idaho to Utah, and I was annoyed when parts of Idaho and Utah sold their regular "85" gas at the same price as the 87 I was used to. The 87 became midrange gas and 90 was premium. In some parts of Utah, I think I even remember seeing an 83.5, 85, 87 as regular, mid and premium.

I also moved, by car, from Idaho to Michigan. There were parts of South Dakota that premium 93 octane was actually cheaper than the regular 87 octane at the same gas station. I asked the gas station attendant if their prices were correct, and they looked back at me funny and said, "yup".
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Joined: 02 Dec 2010
Posts: 18
Location: Quantico, Virginia
Buddy 150, Yamaha R3

PostPosted: Fri Jun 16, 2017 10:08 pm    Post subject: Reply with quote

I use regular per owner manual, which in VA is 87 octane and 10% ethanol. Have over 24,000 miles in 7years with zero issues and good performance. I do make sure in the winter that I keep some sort of fuel additive/preservative in the gas (Startron, Seafoam, or Sta-bil) and try to run errands on it every couple weeks regardless of winter.
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