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MACDADDYBMWR1200RT
06-10-2007, 03:39 PM
Hey I've got a good question for Y'all, if BMW recommends 91 or better octane for the R1200RT, could you run 94 octane Ethanol 85 in it?

Tom K.
06-10-2007, 04:55 PM
Hey I've got a good question for Y'all, if BMW recommends 91 or better octane for the R1200RT, could you run 94 octane Ethanol 85 in it?

Actually, BMW recommends 93 pump octane. So let us know how your RT runs on E85.

deilenberger
06-11-2007, 03:00 AM
Hey I've got a good question for Y'all, if BMW recommends 91 or better octane for the R1200RT, could you run 94 octane Ethanol 85 in it?I wouldn't do that. The fuel system wasn't designed with E85 in mind.. It might run - for a while (and where you you find 94 octane E85?)

MACDADDYBMWR1200RT
06-11-2007, 10:41 AM
In Kansas at the pump, the octane label says 94. What's interesting is that the manual is unclear as to what you can run in your bike. Even though it recommends 91 or better octane, it states that you can run other grades with different results, or something like that ( I don't have manual here to look at.)

greenwald
06-11-2007, 12:03 PM
Recently attended a Tech Session at my BMW dealer for oilheads. Subject of fuel was discussed, and basically the advice was as follows:

Avoid any ethanol fuel greater than 10% in oilheads (2005 or newer) and use premium fuel (octane ratings may vary but premium fuel recommended).

While the engine computer/oxygen sensors can 'compensate' for medium-grade fuels with lower octane ratings, you've bought the 'swiss watch' of motorcycles - don't get your batteries for it at the Dollar Store.

Ride Alert!

RIDERR1150GSADV
06-11-2007, 01:21 PM
IIRC most 'older' BMW's are designed for use of 89 octane gas with perhaps the new K engines for higher rated octane gas.
I have run all my bikes , boats and cages on 87 or 89 octane and never had any issues. I also rarely redline the engines either or expect maximum power from them running this type of fuel. Spending extra $$ on higher octane is a waste of money if the engine is not designed for it. If you take it easy on the engine(s), you can get away with a lower octane fuel. If you do hear pinging than you need to step it up a notch from what you have been using. Higher octane does NOT provide more power. It is a anti-knock index not a HP index. Just my 0.02 cts. YMMV.

100394
06-11-2007, 03:40 PM
IIRC the biggest problem with E85 fuel is that an ethanol content of more than 10% can damage rubber components in the fuel system. Many automobiles cannot run ethanol for this reason. I would play it safe and avoid it.

Tom K.
06-11-2007, 04:38 PM
IIRC most 'older' BMW's are designed for use of 89 octane gas with perhaps the new K engines for higher rated octane gas.
I have run all my bikes , boats and cages on 87 or 89 octane and never had any issues. I also rarely redline the engines either or expect maximum power from them running this type of fuel. Spending extra $$ on higher octane is a waste of money if the engine is not designed for it. If you take it easy on the engine(s), you can get away with a lower octane fuel. If you do hear pinging than you need to step it up a notch from what you have been using. Higher octane does NOT provide more power. It is a anti-knock index not a HP index. Just my 0.02 cts. YMMV.

My 1976 R75/6 was designed for the 95 pump octane available in those days. It would detonate badly above 4,000 rpm on 92 octane which is why folks compensated with thicker base gaskets or dual plugged heads in the early 1980's when U.S. octane began to decline.

And yes, higher octane does provide more power if the engine is designed for it. The hexheads are and use a knock sensor to adjust the timing for lower octane gas, reducing both power and fuel mileage. The owner's manual for my '06 RT clearly claims 110 hp when using 98 RON octane fuel - 98 RON being equivalent to 93 (R+M)/2. It also specs 101 hp when using 91 RON (equal to our 87 pump.

njnear
06-12-2007, 01:48 AM
12:1 pistons.... I think 91 is a little low even though the manual says it's OK. I avoid putting anything in it that's less. Yes the computer will keep it from spark knocking, but I wouldn't chance it on a regular basis.

As for the E 85, the seals/gaskets etc. won't handle all the alcohol (as stated above). E 85 is a different density than gasoline, so your metering system (not carburation) will likely not function properly. On top of that you'll get about 2/3 of the BTU's of gasoline and performance would suffer (including gas mileage).

screamineagle
06-23-2007, 01:50 PM
I am not an expert on fuel but what I have heard is the E85 fuel is much less efficient so that even though it is cheaper per gallon, when you do the calculations it cost the same per mile as galoline. If that is true (I don't know) why use it.

thartman
05-18-2008, 09:57 PM
I sure notice it. I get 250 miles on a tank full of 93 octane but less than 170 miles if I have to use a lower octane. I do run at between 4,000 rpm and 5,000 rpm so maybe that hurts me. I was running on empty yesterday and filled it up with 91 octane then at half a tank topped off with 92 octane the highest I could find. Finally found a station with 93 and topped it off again. I ended up getting 164 miles on that tank before my "42 miles to go" warning came on.

I can repeat it every time, which I try not to do but it is hard to find 93 octane so I get to test it more than I like.

cjack
05-18-2008, 11:21 PM
Hey I've got a good question for Y'all, if BMW recommends 91 or better octane for the R1200RT, could you run 94 octane Ethanol 85 in it?

NO. BMW specifically said (in some SB that I recall) they will not be responsible for faults caused by E85 and recommends a maximum of 10% Ethenol.

grafikfeat
05-18-2008, 11:40 PM
E85 eats gaskets, gasket sealants and rubber.

I ride a 2002 R1200c and run 87 octane. When I was using 89 and above I got 37-40 mpg. I went to 87 it went up to 43-48 and even broke the 50 mpg mark. It won't happen on one tank so run about three and you will see a change. If you get pinging go back to what you were running. But there is NO need to run hi-test. Waste of money.

But for me... I'll put that nickel in MY pocket before I give it to the rat bastard oil companies.

greenwald
05-19-2008, 12:25 AM
We have that E-85 crap here in WI.

15% gasoline, 85% 'corn crap.'

Big loss of power & harsh on seals and gaskets.

Avoid it like the plague!

easy
05-19-2008, 12:34 AM
IIRC the biggest problem with E85 fuel is that an ethanol content of more than 10% can damage rubber components in the fuel system. Many automobiles cannot run ethanol for this reason. I would play it safe and avoid it.

+1

I would not run any ethanol unless absoluty necessary.

If you're in an area of the country where you have to use it, I would start planning on having the rubber seals and gaskets replaced.

Easy :german

cheesewhiz
05-19-2008, 01:56 AM
We have that E-85 crap here in WI.

15% gasoline, 85% 'corn crap.'

Big loss of power & harsh on seals and gaskets.

Avoid it like the plague!


HATE THE E-85!!!!! :banghead

Your local Quik Trip has Top Tier premium with NO ETHANOL.

I'm not sure, but I think the mandate for ethanol use is for regular grade with no demands for it's use in the higher grade fuels.

The law states that the ethanol "mix" fuel shall be clearly marked on the pump. Keep your eyes open for the clean stuff.

Hope this helps.

:thumb

rmeisen
05-19-2008, 11:37 AM
I sure notice it. I get 250 miles on a tank full of 93 octane but less than 170 miles if I have to use a lower octane. I do run at between 4,000 rpm and 5,000 rpm so maybe that hurts me. I was running on empty yesterday and filled it up with 91 octane then at half a tank topped off with 92 octane the highest I could find. Finally found a station with 93 and topped it off again. I ended up getting 164 miles on that tank before my "42 miles to go" warning came on.

I can repeat it every time, which I try not to do but it is hard to find 93 octane so I get to test it more than I like.

I have the unique opportunity to travel 600 miles each weekend over the same route. I have been doing it for over 2.5 years and been able to really measure some of these things (you really reach for things to do after the first year or so..). I had an '04 Rt that got 48-49 MPG (dino oil, 93 octane). I changed to 89 Octane and it went down to 43-44mpg. it was a $.10 savings for the lower octane, less than 2.5% (gas was 2.60-2.80 or so then. remember the good ole days?). Since it was a 10% increase in mileage, I stayed with the higher octane. I changed to synthetic oil, got another 10% increase in Mileage. I was consistently getting 52-53 mpg, measure/averaged over 10 tank batches. I have an '07 RT now and am seeing similar results, although so far my mileage is looking like 55-56 on Premium/dino oil. You may get different results but that's what I got.

ANDYVH
05-19-2008, 11:38 AM
The problem with the "rubber" components is the water in ethanol in the high temperature environment of an engine literally attack the rubber and causes it to age quickly and crack. By high temperature I mean anything above 140 degrees and up to the boiling point of water.

There is no true "rubber" on our bikes. It is a synthetic rubber like Neoprene, Nitrile, EPDM or other blended synthetic rubber. Nitrile, Buna-N (Viton) are the most common synthetic rubber materials for seals such as o-rings. Water at temperatures above 140 degrees F is actually very nasty on Nitrile seals in constant exposure to water in those conditions. Vehicles with fuel systems set up for E85 use silicon, EPDM, or blended Nitrile/EPDM seals to stand up to the high temp water component of ethanol fuels.

But also given that E85 has less potential energy per gallon than does gasoline, we gain nothing using E85 because we get less performance and mileage for the slight savings at the pump. So you end up buying more of it to make up the difference.

BeemerMike
05-21-2008, 02:20 PM
Wow, a lot of interrelated ideas floating around here!

Just a few "basics" to keep in mind as this thread progresses:

1. Gasoline blending is a VERY complex process, involving the mixing and balancing of a large number of different hydrocarbon compounds and additives . . . each with different properties, benefits, and detriments . . . to achieve the desired product result. This makes it more difficult to directly compare one gasoline to another, especially if you switch between brands, because you cannot be sure of the other differences besides octane rating that may be affecting your comparison (e.g., the exact ethanol content).

2. Octane and Power (energy) are NOT the same thing. In fact, I believe that the higher octane gasolines actually have a little LESS energy per gallon than the lower octane gasolines, due to the different mixes of hydrocarbon compounds. Hydrocarbon compounds with a higher octane rating do not necessarily have a higher energy content/density.

3. MTBE (methyl-tertiary-butyl-ether) and ethanol (what replaced MTBE) are BOTH octane boosters and oxygenates. Adding ethanol to gasoline INCREASES the octane rating (although it lowers the energy content - see #4 below).

4. Ethanol has LESS energy per gallon than does the base gasoline blend. The more ethanol you add to gasoline, the LESS energy per gallon you will have. E85 has less energy per gallon than does E10 (90% gasoline-10% ethanol). Therefore, in general, you will travel farther on a gallon of E10 than you will on a gallon of E85 (i.e., more MPG).

5. Some engines (with knock sensors and sophisticated engine management systems) can take advantage of a higher octane gasoline to INCREASE the EFFICIENCY of using the available energy in the gasoline (e.g., timing advance), with the result that you will get more HP and MPG with a higher octane gasoline than with a lower octane gasoline. Absent those sophisticated systems (or you manually making adjustments to your engine), there should be no advantage to using a higher octane gasoline than what is required to avoid "knocking" (assuming the gasolines are the same in all other respects, which is not always easy to know). This is why "high performance" engines need higher octane gasoline . . . not because the gasoline has more energy, but because the octane is needed to avoid knocking with the more aggressive characteristics of the engine (higher compression ratio, advanced timing, etc.).

6. Ethanol can attack certain kinds of "rubber" in the fuel system AND ethanol absorbs water - both directionally bad for your engine. Engines certified for E85 use different rubber compounds that can stand up to the ethanol content than can other engines. The engine manufacture specifies what ethanol content the engine can use.

OK . . . go!

The_Veg
05-21-2008, 06:40 PM
HATE THE E-85!!!!! :banghead

Your local Quik Trip has Top Tier premium with NO ETHANOL.

I'm not sure, but I think the mandate for ethanol use is for regular grade with no demands for it's use in the higher grade fuels.

The law states that the ethanol "mix" fuel shall be clearly marked on the pump. Keep your eyes open for the clean stuff.

Hope this helps.

:thumb

Down in my neck of the woods there is one big sticker per pump (not per grade) indicating that "fuel may contain up to 10% ethanol," so I generally assume that I'm getting 10% in all grades. MPG results seem to bear this out.

danalbertson
05-21-2008, 10:14 PM
E-85 ethanol is used in engines modified to accept higher concentrations of ethanol. Such flexible-fuel vehicles (FFV) are designed to run on any mixture of gasoline or ethanol with up to 85% ethanol by volume. There are a few major differences between FFVs and non-FFVs. One is the elimination of bare magnesium, aluminum, and rubber parts in the fuel system. Another is that fuel pumps must be capable of operating with electrically conductive ethanol instead of non-conducting dielectric gasoline fuel. Fuel injection control systems have a wider range of pulse widths to injection approximately 40% more fuel. Stainless steel fuel lines, sometimes lined with plastic, and stainless steel fuel tanks in place of terne fuel tanks are used. In some cases, FFVs use acid-neutralizing motor oil. For vehicles with fuel-tank mounted fuel pumps, additional differences to prevent arcing, as well as flame arrestors positioned in the tank's fill pipe, are also sometimes used.[

http://en.wikipedia.org/wiki/E85

DocZ
05-22-2008, 02:25 PM
Sadly I drive car on "bidness" around 40K/yr. No problems with 10% corn likker gasOline in the Pilot (aka Hondapottamus - sorry, Keith W!) or the Mini Cooper S.

I put myself in situation a couple of times to use the 10% likker stuff a couple of times in my R12RT with no problems.

My SV1000S seems to not care what swill I put innit.

But re the 85% likker. I'll let one of you brave souls try - I'll watch while YOU report!!! :lurk :lurk :lurk :lurk :lurk

Tom K.
05-23-2008, 11:11 PM
I have the unique opportunity to travel 600 miles each weekend over the same route. I have been doing it for over 2.5 years and been able to really measure some of these things (you really reach for things to do after the first year or so..). I had an '04 Rt that got 48-49 MPG (dino oil, 93 octane). I changed to 89 Octane and it went down to 43-44mpg. it was a $.10 savings for the lower octane, less than 2.5% (gas was 2.60-2.80 or so then. remember the good ole days?). Since it was a 10% increase in mileage, I stayed with the higher octane. I changed to synthetic oil, got another 10% increase in Mileage. I was consistently getting 52-53 mpg, measure/averaged over 10 tank batches. I have an '07 RT now and am seeing similar results, although so far my mileage is looking like 55-56 on Premium/dino oil. You may get different results but that's what I got.
As BMW quotes 101 HP on 87 octane vs. 110 on 93 for the 1200RT, I always suspected that there would be at least an 8% drop which would make it cost effective to stay with premium. Thanks for actually proving that theory.
Tom

blast54
05-25-2008, 03:59 AM
As BMW quotes 101 HP on 87 octane vs. 110 on 93 for the 1200RT, Tom


Where does BMW quote this stat?

swall
05-25-2008, 01:17 PM
Engines that are set up to run on E-85 have a sensor( conductivity based, I believe) that determines the chemical make-up of the fuel so that the computer knows whether it is dealing with ethanol or gasoline. This dictates how much fuel is supplied to the injectors. So, if you put E-85 into an engine that is not equipped with the fuel sensor, the computer will flow fuel to the injectors thinking that it is gasoline. This either will not send enough fuel through the injectors or will result in a screwed up mixture. An engine may also need bigger injectors for E-85 compared to gasoline.

The_Veg
05-26-2008, 04:35 PM
As BMW quotes 101 HP on 87 octane vs. 110 on 93 for the 1200RT, I always suspected that there would be at least an 8% drop which would make it cost effective to stay with premium. Thanks for actually proving that theory.
Tom

So what do you figure HP costs? Without quatifying that, I don't get the 'cost-effective' part. Now attack it from an MPG standpoint and you might be onto something.

gulfcoastbeemer
06-03-2008, 02:39 AM
Octane rating (http://www.madabout-kitcars.com/kitcar/kb.php?aid=124) methods...
In most countries (including all of Europe and Australia) the 'headline' octane that would be shown on the pump is the RON: but in the United States and some other countries the headline number is the average of the RON and the MON, sometimes called the "roaD Octane Number" or DON, or (R+M)/2. Because of the 10 point difference noted above this means that the octane in the United States will be about 5 points lower than the same fuel elsewhere: 87 octane fuel, the "normal" gasoline in the US and Canada, would be 92 in Europe.

BeemerMike
06-03-2008, 03:23 AM
I noticed a slight reduction in fuel mileage with the E-10. It seems that in the past year here that the 10% ethanol stickers are appearing everywhere. I went on a 500 mile trip through western Wisconsin last week and couldn't find any station that didn't have ethanol in their premium.

Ethanol has less energy per unit volume than does the base gasoline, therefore E-10 has less energy per gallon than E-0 . . . the result is a little less mpg with E-10 (maybe a few percentage points).

Ethanol is the oxygenate required by federal law for RFG, and replaced the MTBE, and satisfies the ethanol (renewable fuels) mandate in the federal law. Bottom line - until the law changes, you'll just have to get used to it, but be careful not to get gasoline that has more than 10% ethanol.

Sorry.

ch2ous
06-03-2008, 11:48 AM
My last tank of Hess 93 w/ E-10 got me approx 45mpg. That was accomplished by laying off the other half of the throttle and keeping the needle between 2.5 and 4 grand. I gassed up at a nearby Mobile yesterday where I did not see any ethanol stickers on the pump. Unfortunately the last 60 miles where a bit of a romp so I may have blown the consistency of my very unscientific experiment. :rolleyes but can you blame me?
I'm just cresting the 3k mark on the odometer, can I expect to see better mileage or is there a great deal more breaking in to do on this boxer? I understand that synthetic oil shouldn't be used until the 12k milestone but from what others are saying that should have a significant impact.