Out of gas...

[Sander Abernathy]

Running out of gas isn't newsworthy to be sure but it happened to me last night. Fortunately, I ran out at the top of a very long hill and a gas station was located at the bottom of the hill. Coasting was required but not pushing.

I disclose my stupidity because there were a couple of interesting differences between the 2011 and my previous 2009.

I think the 2011 has less range than the pre-2011's. That tank of fuel lasted me only 175 miles. All of the riding on this tank was in-town and included a bit of very slow stop and go traffic. However, I regularly covered more than that on a tank on my 2009.

MPG per the computer on this bike has stayed right around 37 mpg. On the last bike it was almost always 39mpg. I'm very skeptical of the reported MPG for two reasons. First, it is my understanding that a gas gauge on a motorcycle is, at best, an estimate. If the amount of fuel is not precisely known, how precise can the calculated MPG be. Second, I'm very wary of the odometer on the 2011s. Mine was delivered by the dealer with 9 miles on the odometer and as I recall 14 miles on the Trip II odometer. I've never reset the Trip II and the difference between the odometer and the Trip II odometer continues to increase. Last I checked it was 80 miles. Since Miles Traveled divided by Change in Fuel Level equals MPG and I don't trust the level of precision of either miles traveled or change in fuel level, I'm skeptical of MPG.

I know the low fuel warning light didn't illuminate until after the bike started sputtering. I am pretty sure but not certain that the low fuel warning light illuminated before the bike died completely causing the idiot lights on the dash to all light up but I'm not certain. I won't be relying on the low fuel warning light in the future to justify not refilling when the trip odometer tells me the time has come.

I was only able to get 5.3 gallons into the tank when I filled up and that included a bit of overfilling. Perhaps my memory is bad but I'm certain I could put more into the tank of the 2009.

Until experience tells me otherwise, I assume I need to hit the pump before 160 miles of daily commuting in the future.

[websterize]

It's happened twice to me, once in the middle of traffic, middle lane, uphill, 90 and humid. So I refill after ~150 miles when commuting and ~200 miles when touring.

Like you, I'm skeptical of the mpg/residual range readouts, and I pretty much ignore the residual range. The fuel sensor strip, which is likely a critical part of the calculations, is not reliable — tripmeters much more so.

[roger l]

The computer does not use the fuel strip for the calculation of the MPG. The fuel strip has gone out on my bike and i am waiting for the part to come in to have it replaced. The MPG function on the computer still works and is accurate. The distance to empty display does not work with out the fuel strip. I have been using the trip odometer for fillups. I start looking for gas arround 175 miles. I will take the bike in 5/6/11 to get the strip replaced.

Roger L

[angellr]

Like Websterize, I have refueled at about 180-200 miles on the trip meter. I reset this EVERYTIME, as I have never put alot of trust in the 'puter to tell me when to refuel. Amazingly, at about 200 miles the other day, I put 5.2 gallons in the tank right to the top (sort of freaked me out) and have made a mental note to err on the side of about 150-175 or so for my future refueling needs, except when I am slabbing it at a constant speed.

[jess]

First, it is my understanding that a gas gauge on a motorcycle is, at best, an estimate. If the amount of fuel is not precisely known, how precise can the calculated MPG be.

As mentioned above, it's not dependent on the fuel strip to determine MPG. The OBC is almost certainly measuring the injector pulse widths each time the injector squirts and calculating MPG based on the known fuel delivery rate of the injector. In general, that approach is fairly accurate.

Second, I'm very wary of the odometer on the 2011s. Mine was delivered by the dealer with 9 miles on the odometer and as I recall 14 miles on the Trip II odometer.

That's interesting! I note that 9 miles == 14.48 kilometers. I'm wondering if your display is in some weird mode that it's not supposed to be in, with the odometer in miles and the trip meter in kilometers. Seems unlikely, but no more so than having an odometer and a tripmeter that can't agree.

I've never reset the Trip II and the difference between the odometer and the Trip II odometer continues to increase. Last I checked it was 80 miles.

Can you give us exact numbers for both as it stands right now? Might validate the miles / km theory. Or dispel it. Either way, it's fascinating.

I was only able to get 5.3 gallons into the tank when I filled up and that included a bit of overfilling. Perhaps my memory is bad but I'm certain I could put more into the tank of the 2009.

I managed to stuff 5.43 US gallons in the tank of my 2009 the other day. I was down to about 19 miles left (according to the computer). So pretty close to empty.

[red baron]

I ran out of gasoline one time and was able to coast into a filling station. I filled the tank up to the rim and I was able to add 5.62 gallon having the bike on the sidestand. Frankly I dont trust the computer and strictly go by miles driven. Anyway normally I fill up at about 190 and one rare occasions at about 210 miles and according to the computer my average speed ranges in the low to mid 60 mph. Usually I can add 4.8 to 4.9 gallons by filling up to the rim. Interestingly enough the instruction booklet mentions tank capacity: 4.6 usable gallons. I guess when you fill up to the rim the computer gets confused and therefore gives wrong readings. Obviously one has to consider driving conditions when one makes decision when to fill up.

[ka5ysy]

Hi Sander:

A couple of things you are not factoring into the mileage equation is that new bikes are going to get less mileage than one that is run-in. My 2007 initially started out around 37-40 mpg and improved over time after about 5,000 miles and now delivers around 45-55 mpg depending on wrist control and variables such as gas mix.

You will definitely see a decrease in MPG when you have a lot of alcohol in the fuel simply because it is less energy-dense than gasoline. Seasonal changes in fuel formulation due to the idiots in EPA also cause grief with MPG. I can tell when our winter/summer gas is changed simply because the MPG dramatically changes within a couple of weeks in late spring and late fall.

[Sander Abernathy]

Hi Sander:

A couple of things you are not factoring into the mileage equation is that new bikes are going to get less mileage than one that is run-in. My 2007 initially started out around 37-40 mpg and improved over time after about 5,000 miles and now delivers around 45-55 mpg depending on wrist control and variables such as gas mix.

You will definitely see a decrease in MPG when you have a lot of alcohol in the fuel simply because it is less energy-dense than gasoline. Seasonal changes in fuel formulation due to the idiots in EPA also cause grief with MPG. I can tell when our winter/summer gas is changed simply because the MPG dramatically changes within a couple of weeks in late spring and late fall.

I'm pretty convinced that my wrist is more enthusiastic than most on this board. That's why I always seem to have low numbers. Also, I do very few highway miles. I generally ride the bike in-town commuting or I drive to the mountains to find the good roads. The only highway miles I travel are the 60 or so between home and the mountains and that's infrequent.

I agree that the mileage should improve as a new bike is broken in. However, over the 7,000 miles I had my 2009 the change was no more than 1 or 2 miles per gallons. Of course that was the first 7,000 miles I had ever ridden. During that time, I went from being unqualified to leave a parking lot to doing a wheelie and flipping myself off the back of the bike. (In other words, I was still unqualified to leave the parking lot.) Could more aggressive riding have mitigated any improvements in the mileage delivered by the bike? Sounds likely don't you think? LOL

Ethanol would certainly explain it but I haven't seen any seasonal changes. I do know there is an Atlanta specific summer blend. I wonder what goes into that.

I've always assumed that since I'm not in the corn belt the level of ethanol in our gas is relatively low. This is the bible belt rather than the corn belt after all so we favor putting bibles in our gas over ethyl alcohol which, as we all know, is a product of the devil. However, Atlanta is on the EPA black list due to too many annual bad air days. Maybe our gas is actually ethanol rich because of the bad air problem and because, as we all know, the EPA is an agent of the devil.

[AncientMariner]

I just took a 330 mile round trip to Vermont to the Yankee Beemers Frosty Nutz campout.
OBC claimed 54 mpg on the ride up (Shell @$4.19/gal) and 51 on the ride back (Exxon/Mobil @$4.09/gal). Just coming up on 2,000 miles. Can't wait to see how she performs after she's broken in.

Bruce

P.S. Refilled and manually calculated mileage for return trip: 2.836 gallons for 153.9 miles = 54.27 mpg

[Bob Ain't Stoppin']

Just another fun data point. My '08 with 15k miles on it just got 260 miles on a tank. Put 5.5 gallons in it for the refill. I'm happy. With a replaced fuel strip, the computer seems to be giving pretty accurate info.

[Sander Abernathy]

Just another fun data point. My '08 with 15k miles on it just got 260 miles on a tank. Put 5.5 gallons in it for the refill. I'm happy. With a replaced fuel strip, the computer seems to be giving pretty accurate info.

260 miles! When you say Bob Ain't Stoppin, you aren't kidding.

I assume your tank wasn't completely empty and you were able to put 5.5 gallons in the tank. Mine was completely empty and I could only get about 5.3 in mine. Me thinks the capacity might have shrunk. I'm going to look at the manuals for the 2009 and the 2011 and see if the stated capacity in the manual has changed.

I don't have either bike anymore though I hope the 2011 is repairable. I do still have the manuals as a keepsake though and I make vroom, vroom sounds when I'm riding the subway.

[xprof]

I got a 260-mile tank and put in 5.8 gallons, according to the pump. What this means to me is not that our bikes are different, but that some gas stations are cheating us...

[rockbottom]

Hmmmm. First weekend I had my bike I filled it up and then rode until the the light came on. It was 220. So now I always use the fuel gauge on my GPS set to 220.

[tinytrains]

I got a 260-mile tank and put in 5.8 gallons, according to the pump. What this means to me is not that our bikes are different, but that some gas stations are cheating us...

Hi Mike,

I think the variable here is how full is full? Do you stop at the bottom of the neck or keep going.

Scott

[2wheels]

My 2011 returns 57mpg at 950 mls.

Does anyone know if the OBC distinguishes between US and Imperial gallons?

My 57 mpg(Imp) equates to 47 mpg US and it seems to me that if members are getting an indicated mpg around 55 then the OBC must use Imperial. Obviously if you are using brim to brim calculations then it will be accurate for the type of 'gallons' you use!

For the record, my tank capacity is specified as 18 litres. This equates to 4.75 US and 3.95 Imp..

[Bob Ain't Stoppin']

[quote=I think the variable here is how full is full? Do you stop at the bottom of the neck or keep going.

Scott[/quote
I agree with this. I stuff as much gas in there is I can. Right to the top, as there is no charcoal canister to worry about (have no idea where it went )