E85Forum.com

jc_puckett · Joined: 12 Dec 2005 Posts: 4 Location: Perryville, MO

I am waging a campaign to be selected as one of 90 riders out of 5,000 qualified riders to participate in the 2007 Iron Butt Association Motorcycle Endurance Rally. E85 is my “hook” to avoid the lottery (e.g. previous IBR finishers who want to participate again get first shot. There are a few slots reserved for IBR virgins who have an unusual and/or interesting basis for wanting to participate in the biannual rally … that would be my E85 entry application).

http://www.ironbuttrally.com/IBR/default.cfm

I am also directly involved in the design and construction of three (3) motor fuel ethanol production facilities – one utilizing the ICM batch fermentation process and two utilizing the Vogelbusch continuous fermentation process.

So my question is “How many miles per gallon will I get on my BMW R1150RT burning E85 ethanol (assuming correct modifications designed and installed with BMW Motorrad NA input) if I recently got 36.55 mpg burning premium gasoline while maintaining a moving average speed of 75.22 mph (GPS miles; not BMW odometer miles) on my Bun Burner Gold 1500 mile ride from Burlington, Vermont on October 16-17, 2005?

E85 is 85% ethanol by volume.

Ethanol has a density of 6.61 lbs/gallon and the gasoline averages about 6.2 lbs/gal, so the blend is 6.55 lb/gal. The ethanol is 85.8% by weight and the gasoline is 14.2% by weight.

The stoichiometric combustion of the ethanol:

C2H6O + 3.5 O2 + 13.17 N2 = 2 CO2 + 3 H2O + 13.17 N2

The gasoline combustion can be represented by:

CH2 + 1.5 O2 + 5.64 N2 = CO2 + H2O + 5.64 N2

which is a convenient simplification of the EPA accepted average H/C ratio for gasoline

CH1.85 + 1.4625 O2 + 3.76 x 1.4625 N2 = CO2 + 0.925 H2O + 5.5 N2

Since the weight of CH2 is 14, and the weight of ethanol is 46, the combustion of a blend that is 14.2% by weight gasoline can be represented by adding this to the ethanol combustion equation:

0.544 CH2 + 0.816 O2 + 3.068 N2 = 0.544 CO2 + 0.544 H2O + 3.068 N2

The sum of the two equations is:

C2H6O + 0.544 CH2 + 4.316 O2 + 16.238 N2 = 2.544 CO2 + 3.544 H2O + 16.238 N2

The overall air fuel ratio for E85 is:

Weight of the air: (4.316 x 32) + (16.238 x 28) = 592.8
Weight of the fuel: 46 + (0.544 x 14) = 53.6
A/F = 11.06

The overall air fuel ratio for gasoline is:

Weight of the air: (1.4625 x 32) + (5.5 x 28) = 200.8
Weight of the fuel: 12 + 1.85 = 13.85
A/F = 14.5

14.7 is a better average value, but the calculation above is based on what EPA allows manufacturers to use when doing emissions testing.

Energy content of E85:

The average energy content of a gallon of gasoline = 125,000 btu

The energy content of a gallon of ethanol = 84,400 btu

The average energy content of a gallon of E85 = 90,490 btu

Therefore, it takes 1.3814 gallons of E85 to equal the energy in 1.0 gallons of gasoline.

E85 air fuel ratio of 11.06:1 versus 14.7:1 for gasoline = 32.91 % more E85 by weight.

The National Ethanol Vehicle Coalition claims a 5% to 20% drop in fuel economy.

http://www.e85fuel.com/e85101/faqs/range.php

Based on the above chemistry, how can this be true?

Please don’t misconstrue where I am headed with the above question. I am a friend of ethanol.

Jim Puckett, PE
Chemical Engineer
Robinson Construction
2411 Walters Lane
Perryville, MO 63775
(573) 547-8397 x125
(573) 547-8398 fax
_________________
Jim Puckett, PE
Robinson Construction
Perryville, MO 63775
BMW R1150RT
Iron Butt Association # 24142

hotrod · Joined: 19 Apr 2005 Posts: 872 Location: Colorado

Mileage is not directly related to the fuel energy. You also have to consider drivability and engine effeciency issues.

For example an engine tuned to run on E85 will generate about 5% more power and torque than it did on gasoline, that means you will spend less time at higher throttle settings and be able to pull longer gears on light throttle opening.

If you can change the engine set up by either changing the physical compression ratio or using more ignition advance (without over advancing it for best economy) you can also gain thermal effeciency, ie the engine gets more useful work out of a given number of BTUs of fuel energy.

Also since ethanol tends to burn cooler at proper mixtures you may also be able to run leaner fuel air mixtures than you could get away with on gasoline.

Add all those together and you get a non-linear relationship between raw fuel energy and fuel milage with is actually a measure of "useful work"

Larry

specialgreen · Posted: Wed Jan 04, 2006 11:27 pm Post subject:

Amount of energy stored in a fuel is only loosely coupled with the rear-wheel HP Smile

. For example: water injection can increase power, but water contains very little energy.

My Suzuki GS500 has a compression ratio of 9:1. With E-85, I could increase compression to 12:1, and should effect a nearly 30% increase in RWHP. Wth proper gearing, that could yield an increase in MPG, despite the reduction in energy.

Having ridden 3 seasons on E-85 (at stock compression), my best mileage for a morning ride was 42.6mpg (across about 4 gallons). I can keep MPG over 40 most of the season. Typical mileage for this bike is maybe between 48 and 58mpg.

That said, E-85 availability may be an issue on an Iron Butt ride. I have to carry E-85 with me, just to ride into the next state (2.5 gal. cans in the tank bag and tail bag, and I'm good for 360 miles):

PS-I've always wanted to start a casual version of the Iron Butt Association. Our rides would be 500 miles in 12 hours, and we'd be called the Half-Assed Association Wink

jc_puckett · Joined: 12 Dec 2005 Posts: 4 Location: Perryville, MO

Does anyone have experience with either the Dynojet Power Commander or Techlusion fuel injection recalibration kits?

I am considering converting my BMW R1150RT to burn E85 ethanol/gasoline blend. I will need to reduce the air:fuel ratio from approximately 14.5:1 to 11:1.

If this works out, I may spend some real money and get Wiseco to make me a pair of 13.5:1 compression pistons to optimize the engine for ethanol.
_________________
Jim Puckett, PE
Robinson Construction
Perryville, MO 63775
BMW R1150RT
Iron Butt Association # 24142

pwr · Joined: 08 Dec 2005 Posts: 4 Location: Ann Arbor, MI

Jim, congrats on the BBG. I'm not an IBR veteran, but I've done a number of Iron Butt Association rides, including a San Diego to Galveston Bun Burner Gold and a 41-hour 50cc (for those listening in, that's documenting a ride of 1500 miles in less than 24 hours, and coast-to-coast in less than 50 hours.) I've also taken second place in the Tarbutt rally, back in 1998. Paul Taylor, the 2003 IBR winner, beat me by 7 points. I've pretty well written off the Big Dance because, well, mixing competition with fatigue doesn't seem like such a good idea to me anymore, and it's a gawdawful expensive rally too. One of my IBR veteran friends says, "eleven days, eleven thousand dollars."

I don't think your range is going to be anything near the issue that availability is, but the first issue feeds into the second.

Let's look at range first. I suppose 35mpg is largely a worst-case scenario since your bike should be getting in the neighborhood of 45mpg at elevated highway speeds, and you won't be keeping anything near that kind of moving average in the IBR. Still, you will have a 20 percent efficiency drop, at best, in fuel mileage, so let's say 28mpg. You have a fuel capacity limit of 11.5 gallons, so assuming you want a slight cushion you have a 300 mile range. This completely negates any auxiliary fuel capacity advantage--it puts you below stock range of several bikes like the ST1300, in fact.

Second, since you won't have much more than a clue as to where you're going other than the published checkpoints, you are simply not going to be able to find E85 much of the time, and in my experience there are few 24-hour E85 stations. I think we in the midwest have somewhat of a false picture of its nationwide availability.

I applaud you for doing more than your part in increasing its availability, and the picture may well be different in 2007, but here are two current realities: 1) according to the NEVC map right now it's not publicly available at all in the Northeast, which is going to play hell for the all-but-certain Gorham ME checkpoint; and 2) there's only one public station in all of traditionally bonus-rich Texas.

Those two facts alone make your negotiation with Lord Kneebone not a matter of whether you'll use E85 exclusively, but a matter of where and how often. It negates your position for negotiating an increase in aux fuel capacity (which, as I understand it, isn't a safety issue as much as it enforces a stop at least every 400 miles). Even given availability enhanced over what it is today, I'd challenge you to plot a coast-to-coast ride that would have you burning E85 the entire way.

My understanding of rally success is doing everything you can to make the variables constants. The only way you can do this with fuel is riding an efficient bike with maximum allowable capacity. An E85 fuel requirement makes simply getting to a fuel source the overriding concern of your rally. This might have worked when checkpoint-to-checkpoint rides were permitted, but now that you need a minimum number of points to be considered a finisher, the "Hopeless Class" seems to be on its way out. Color me skeptical that you'd be able to amass enough points to finish, now that the bar has been raised significantly.

Interesting discussion, and interesting angle. I'd be interested to hear how your pitch goes. But as of now, even if you get in, I don't think you'd have much of a shot of being a finisher if burning E85 was a requirement rather than an option. I'd be working the "making myself invaluable to the rally staff" angle for getting in, myself. :^)

Phil Ross
Ypsilanti, MI
IBA #3254

specialgreen · Posted: Mon Jan 09, 2006 5:07 pm Post subject:

I've thought of adding some frames where the saddlebags go, to hold a pair of 20L jerry cans. But IBA may prohibit that.

I was envisioning that he'd have some support: a friend driving a fuel truck (or, a truck with some 55-gal cans of E-85 in the back). He'd still have to stop at the required intervals, and would have to buy gas at a gas station for documentation, but might be able to buy a token amount each time (0.1 gallons) or something.

In Minnesota, the association sponsors some rides that let you pick your own path to get to 1000 miles, and you try to pick-up bonus points. They are structured more like a wide-ranging scavenger hunt. That kind of ride could be done on E-85, if you kept to the midwest. But, no, there's no way to do a 4-corners without your own truck following you.

Also, I'd probably start be looking to a fuel-sipping bike. The race has been run on a 250 Ninja before; is there a Comet 250 V-twin now? Even a trusty KLR650 (or a F650/650cs) would give you much more range than the liter bike.

pwr · Joined: 08 Dec 2005 Posts: 4 Location: Ann Arbor, MI

jc_puckett · Joined: 12 Dec 2005 Posts: 4 Location: Perryville, MO

specialgreen · Posted: Sat Jan 14, 2006 11:22 pm Post subject:

Since I'm carbed, with fixed jets, I can't adjust on the fly. My thought was to drill a small hole into the side of each carb venturi. This would create a vacuum leak, and would lean-out my mixture to the point that it would run on gasoline.

I would run vacuum lines from both ports to a small reservoir with a bleeder valve. I'd want the valve where I could fiddle with it while riding. And I'm sure that it would be impossible to set-up, so that it would idle smoothly AND cruise smoothly. For that, it'd be easier to just carry a second set of carbs!

Since you're talking about turbo, I think that others on this forum have written about fiddling with the boost to match the current mixture of ethanol and gasoline:

http://e85forum.com/about57.html

geokoppmann · Joined: 27 Aug 2006 Posts: 2 Location: Santa Fe

Jim & Group;

I've been talking with Dan Lorenzo (supertech) at Full Flex Inc. about a Full Flex Gold conversion unit that is plug & play on my '01 BMW K1200 LT touring bike (land yacht) with 22,xxx miles on the odometer which will permit it to run on 92 octane unleaded gas or E-85.

As soon as we complete the Flex Fuel conversion of my '98 Ford F150 XLT 4.2L V-6 I'm planning to start on the motorcycle so, any input, (postitve or negative), suggestions for data that I should collect would be greatly appreciated. I that works OK, I have another '01 BMW K1200LT waiting in the wings in El Paso to be converted to Flex Fuel capability.

I already have very 2 yrs. worth of detailed mileage figures based on straight line GPS distances not on trip readings, (I also have a comparison of the two distance figures), riding 2 up all the way at altitudes from 4,000' msl to 11,700' msl from El Paso, TX to Steamboat Springs. CO.

Is your bike dedicated to E-85 or did you install a Flex Fuel kit of some kind ?
_________________
George in Santa Fe

specialgreen · Posted: Sat Sep 02, 2006 2:01 pm Post subject:

Mine's dedicated to E-85 (coming-up on 3 years now!). It's carbed, but I've thought of some ways to jury-rig a "limp home" mode on gasoline.