question about 87 octane fuel

[mogle]

have been using 87 octane (regular unleaded) in my new m50 just like the manual says--
seems to run ok and gets around 50 mpg--
my question--
would it benefit performance & mileage to use a higher octane fuel??
what are you guys & gals using in your m50 's??

[Everett Keith]

I use only 93 in my M-50 and I get 53 mpg and better response when in the mountains.

[cjjtulsa]

I tried going up in octane and never really noticed a differnence other than in my wallet. It may be there though and I just didn't notice it.

[jpwM50]

I use 89, you can never go wrong with the middle of the road,,,....well except on a bike.!

[KNIGHTENFORCER]

When I went to pick up my bike, the prep guy at the dealership told me to use 89, the one in the middle...not too low, and not too high....Bike runs great at the present time. 1300 miles so far.

[2kMarauder]

87 octane since i bought it. Never ran anything higher than that...seems to be a waste of money.

[Pinhy]

Originally Posted by 2kMarauder

87 octane since i bought it. Never ran anything higher than that...seems to be a waste of money.

+1...why spend more money than what the manuf. recommends? some cars and bikes specify 93...this one doesnt and runs fine. until someone tells me it is better for the engine or performance, then im running the cheap stuff

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[Edward_Teach]

i have a background in tuning efi systems in cars. not up on motorcycles.

does anyone know if our bikes have a sensor that might pull timing with knock? with all the vinration in v-twins i would think it would not be very sensitive even if it was there.

if so, 93 octane could produce a little more hp by allowing more timing. i know some of the buell guys (air cooled) here run it during the hottest months to cut down on knock and ping.

[conrad]

The stealer told me "only run 93 octane". I've tried both 87 and 93 and can't tell the difference at all other than the additional 30 -50 cents per tank. I will continue to use 87 with some fuel stabilizer over the winter.

[bakdoor]

Originally Posted by conrad

The stealer told me "only run 93 octane". I've tried both 87 and 93 and can't tell the difference at all other than the additional 30 -50 cents per tank. I will continue to use 87 with some fuel stabilizer over the winter.

Yeah, my stealer told me the same thing about the high octane, and I've put nothing but 92 or above since I've had it. Might have to try 89 and see if it makes any difference...

[jkulysses]

My stealer just told me to run 87 in it. I might try 92 next time just to see if it really makes a diff. or not.

[QuacktheDuck]

91 the first tank, what a waste. Used 87 ever since. If the manufacturer says it's good enough, then it's good enough for me. Not like it's a high performance motor with boost or really high compression so I don't think any damage will result from 87.

[axel_2078]

There's a big misconception that higher octane fuels equals higher performance. That's not how it works. There are higher octane levels for engines that have higher compressions. It's not "good, better, best." It depends on what your engine is rated for and what the manufacturer recommends for it. And for that matter, the quality varies among octanes as well. Joe Bob's 91 octane may be dirtier and contain more contaminants than BP's 87 octane. This Citgo's 89 octane may be dirtier than a competitor's 89 octane. If you're using an octane that's rated higher than the compression needs of your engine, you really are throwing your money away. Numerous studies have been done on this, but I'm too lazy to search for them. I'm surprised no one's brought this up already.

[QuacktheDuck]

Originally Posted by axel_2078

There's a big misconception that higher octane fuels equals higher performance. That's not how it works. There are higher octane levels for engines that have higher compressions. It's not "good, better, best." It depends on what your engine is rated for and what the manufacturer recommends for it. And for that matter, the quality varies among octanes as well. Joe Bob's 91 octane may be dirtier and contain more contaminants than BP's 87 octane. This Citgo's 89 octane may be dirtier than a competitor's 89 octane. If you're using an octane that's rated higher than the compression needs of your engine, you really are throwing your money away. Numerous studies have been done on this, but I'm too lazy to search for them. I'm surprised no one's brought this up already.

exactly my point, well said.

[Pinhy]

bottom line: if i dont have that annoying sticker that says "only 92 octane or better" then i am putting the cheap stuff in until the car/bike seems to run bad on it.

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[Everett Keith]

I know that I do not have to put 93 in but when I go into the mountains I can fell the difference. Just my thoughts.

[cjjtulsa]

Whether car or bike, I let the engine determine if it needs it or not - if it spark-knocks, then I up the octane. If not, 87 does just fine.

[stevek]

I don't know how this would apply to the M50, but I know that my owners manual for my car recommends 87 and explicitely states that 89 or 93 not only doesn't help performance but also could reduce performance. I've always followed that recommendation.

[viper94bite]

I used the primium stuff in all my bikes for a while. Then I tried using the 87 in the rauder and after a while I noticed a slight knocking and it was harder to start. So I have gone back to the premium. I figure one or two more dollars a tank is nothing.

[rappidrabbit]

I use Standard(chevron) ,,,,, here the gas is rated at 86, 88, qnd 91 octain ...have been using 88 as the bike requires 87 octain...when I use 87 fron a out of area station cant tell much difference... a friend races cars (own 2 race tracks, and builds race cars) and he told me that Chevron is a cleaner processed gas so will continue to use it....