Gas Octane You Use

[CTB63]

Hello ALL,

The users manual on the C600S stated 89 Octane to be used on the scooter and that's what I've used since owning the scooter...

I searched the forum and see others using a much higher octane than 89, and also mentioned improved gas milage and smoother engine and throttle response...

What Octane do you put into your C600/C650 and why?

 

[Sparkrn]

89 is what I have been using. Though the filler door says to use a minimum of 89, you can use higher. I don't really know the advantage of 91 or so.

 

[Colin J Monteith]

Hello ALL,

The users manual on the C600S stated 89 Octane to be used on the scooter and that's what I've used since owning the scooter...

I searched the forum and see others using a much higher octane than 89, and also mentioned improved gas milage and smoother engine and throttle response...

What Octane do you put into you C600/C650 and why?

While I have used 89 in the last couple fills I do think 91 burns better and gets slightly better mileage. My calculations show it to be about the same cost per mile so don't buy unless it sounds and feels better.

 

[SteveADV]

I use BP 93 because I don't mind paying for extra useless octane . I did put 87 in there this past winter as that is what I use in the KLR and was not paying attention (hmmmm....tall green ugly dual purpose bike and a red maxi-scooter....anybody could make that mistake). Next day my CGT would not start so I bought some octane booster and it ran fine.

 

[exavid]

Double check your owner's manual there's s difference between the MON octane rating the Europeans use and the RON octane used in North America. After checking the difference I use 93 in my GT. Higher octane won't give you more power all it does is prevent detonation or 'ping', which is actually compession ignition similar to what happens in diesel engines. In a gasoline engine which is much lighter built it's hard on pistons and rods. Octane doesn't really effect the amount of BTUs much in gasoline and BTU content is what generates heat which is the name of the game in a heat engine like any internal combustion engine.

 

[justscootin]

Using wickapedia and doing all the calculations I have come to the conclusion that 89 octane is fine. I have used 87 and found the engine runs louder. Gas in Canada may be better gas but I doubt it, it should be the same.

 

[Scorpion56]

Double check your owner's manual there's s difference between the MON octane rating the Europeans use and the RON octane used in North America. After checking the difference I use 93 in my GT. Higher octane won't give you more power all it does is prevent detonation or 'ping', which is actually compession ignition similar to what happens in diesel engines. In a gasoline engine which is much lighter built it's hard on pistons and rods. Octane doesn't really effect the amount of BTUs much in gasoline and BTU content is what generates heat which is the name of the game in a heat engine like any internal combustion engine.

Always 93. I was surprised when the dealer told me to fill it with 93. My Honda had been happy with 87. Then he said, "think about it - it's 3 gallons per fill-up" So that's an extra 75 cents over 91 octane per fill??? It's all about preventing knock/ping.

 

[Gnslngr]

Always 93. I was surprised when the dealer told me to fill it with 93. My Honda had been happy with 87. Then he said, "think about it - it's 3 gallons per fill-up" So that's an extra 75 cents over 91 octane per fill??? It's all about preventing knock/ping.

What he said.

 

[JaimeC]

If your scooter is pinging/knocking, it doesn't need better gas, it needs to be serviced... there's something WRONG. The Sunoco station on the corner is one of the few stations I've found that sells 91 Octane as well as 87, 89 and 93. The GT gets the 89, and the K1200LT gets the 91. I'm not spending one penny more than I have to to these greedy oil companies. The K1200LT just rolled over 190,000 miles on the odometer and is still running great, so I'm not concerned that I "should" be running a higher octane. BMW says it'll run on 91, then 91 it gets. It only gets higher octane when 91 isn't available. Fortunately, 89 is pretty easy to find.

 

[Skutorr]

Your computerized ignition system will give you a bit more timing advance with higher octane gas, which increases power, acceleration and mileage...

 

[JaimeC]

The only thing the computerized system will do is detect knock/ping and retard the timing giving you less power. It doesn't do the reverse.

But hey, it's your money so do with it as you like. Since I average between 16,000 to 18,000 miles a year on PTWs, I'd be wasting far more money if I bought higher octane gas than most of you, I figure. If you don't put those kinds of miles on your bikes then the price difference is a pittance.

 

[wsteele]

Since there is only about 20 cent differance between Reg. And Prem I use premium and the bike gets 55 miles to the gallon I find it is worth it not to get engine knock, I drive about 12000 to 14000 miles a year. On the other hand my Chevy van that I use for work gets 8 miles to the gallon. That's not a typo I get 8 miles to the gallon it is a Chevy 3500 van with a 4.8 litre V 8 I use reg. Gas it has a 33 gallon tank.

 

[exavid]

Octane demand is driven by compression ratios. Period. Most Honda engines especially their larger ones are not high compression engines and don't need higher octane fuel under most conditions. BMW does seem to like to squeeze more power per cubic centimeter from their engines and higher compression is one of the ways they do it. Lower than recommended octane most likely won't ping with modern EFI systems but you will lose efficiency, power and mileage in other words.

 

[JaimeC]

Carbon build-up in older engines can slowly increase compression in them. However, modern detergent gasolines (AND running the engines at their recommended rpms instead of lugging them around in too high a gear) prevents this build up. At 190,000 miles, my K1200LT is still running just fine on 91 octane fuel.

We used to call it an "Italian Tune-Up:" Running the engine in a lower gear than normal and revving the **** out of it. I discovered that the first time I had my old K100 on the track. It had 130,000 miles on the odometer at the time I took Reg Pridmore's C.L.A.S.S. for the first time up in Watkins Glen. He stressed that keeping the bike in third gear for most of the track would give you better throttle management and more control of engine braking to set up for turns. I blew a ton of "charcoal" out of the exhaust the first time out; they thought I blew the engine there was so much black smoke. The mechanic realized it wasn't a problem; the bike was just "clearing its throat."

After that day, the bike ran much much smoother. Even my wife noticed it sitting on the back. That's when I learned the BMW engines were designed to be run at high rpms; you can run them at redline all day long without harming them. Now, I only use top gear on the highway. Not really a choice with a CVT though. We can only trust that the engineers designed them to run at the engine's most efficient rpm.

 

[Scoots you sir]

95, because in Ireland it's either that or diesel. Saves us any agonising decisions at the pumps I suppose...

From what I can tell that would be equivalent of 90 in the US & Canada.

 

[Skutorr]

Not really a choice with a CVT though. We can only trust that the engineers designed them to run at the engine's most efficient rpm.

Actually, they didn't. At full throttle the C-series run under both their torque and horsepower peaks, especially off the line. That's why EVERY member in the Italian C-series forum uses, or will soon install, a different variator or Dr. Pulley sliders. Same problem all stock Tmaxes (till 2012) had...

 

[CTB63]

Hey All,

Thanks for your input....

I'm going to try a higher octane in my next fill up and see if I notice any difference...

 

[TwoPort]

I think I may get 2-3 MPG less by using 87 vs. 91 in California. I've tried it about a month and it "seems less mpg."

 

[JaimeC]

87 is two points too low. I'm not surprised.

 

[tlippy]

All of us in the Silver Eagle motorcycle riding club in Central Oregon go out our way to exclusively use Clear Fuel which is ethanol free. And costs $0.50/gal more.
Most of us ride, or did until I got my C650GT, big Harley rod hogs and every one of us is getting consistently 4 mi. + per gallon vs the old 89 fuel with ethanol.
I bought my C 650 in Eugene, OR and on the way back to Redmond I had to use ethanol fuel. On the trip home which is highway, I got 45 mi/gal. Next fill was ethanol free and mileage has been consistent on 2 tanks of fuel = 52 mi/ gal. I don't care what fuel costs. I'm buying Clear fuel !!!��