Usable fuel?

[Twisties]

Regarding my new to me 1250 GS, the manual claims 5.3 G of usable tank volume, including a 1.1 G reserve.  Today, for the first time I went into reserve, about 5 miles.  I put 4.9G of fuel in.  So I had about 0.5G when it indicated 0 miles remaining.  I got the low fuel warning about 50 miles earlier, but no specific warning when I reached 0, and no negative miles count.  If I hadn't been on miles remaining, I might never have known I was in reserve at all. 

 

On my old RT you get the 50 miles early yellow low fuel warning, the red 0 miles remaining, and then, IIRC there is some indication how far you've gone into reserve.  The 0 miles remaining/red indicator pops up exactly when there are 1.1 G remaining.  

 

Oh, by the way, this is what happens when both Google Maps and the lady at the coffee shop tell you it's 40 miles to the next town and it's really 60+.  :-)

[Twisties]

So, I'm wondering, is 5.3G really the useable fuel quantity, and am I missing something about how to watch the beginning of reserve?

[Dave_in_TX]

If I understand correctly, you were 5 miles past 0 miles remaining. I have never running my 1250 to that point but based on miles remains, mpg, and how much gas I added, 5.3 seems correct to me. However, you need to carefully add gas once you get close to top.

[BrianT]

I haven't run mine past zero miles to find out yet.  But when I've been close to zero miles remaining, I had a similar volume left to what you did.  So, it does seem this is normal behavior.  If that phantom half gallon is usable, that would be nice.

[Twisties]

Today I ran to 2 miles remaining and added 5.05 g to fill.  If it runs out at 5.3 g, I had .25 left.  One of these days I'll carry some extra fuel and find out.  But this seems like way too close.  I think it's 1.1 g left when the initial low fuel indicator comes on, at least assuming I'm calibrated and functioning correctly.  On the plus side, I got 267 miles on that tank, 53 mpg.  The bike said 56 mpg, so not too far off.  The miles remaining are fairly accurate as you approach empty.   I left the house with 48 miles remaining, rode 44 miles, and had 2 miles remaining.   

[Rougarou]

I've gone 25+ miles under zero on the GSA.  Do it fairly regular on both the GSA and RT.

 

This be me:

 

[roadscholar]

If it's anything like a couple German cars I have the computer keeps adjusting miles to empty based on how you drive/ride. If in conserve mode the miles to empty can increase substantially. I think some manufacturers are more conservative than others too, I've pushed it a few times in Mercs and never run out but also learned the hard way not to trust Chevy trucks at least ones from the mid 2000's.

[Skywagon]

Total useable with reserve confuses some folks… the way BMW writes it

Total useable is all the fuel you have. There isn’t a reserve after your 5.3 gallons is gone

[Rougarou]

1 hour ago, roadscholar said:

If it's anything like a couple German cars I have the computer keeps adjusting miles to empty based on how you drive/ride. If in conserve mode the miles to empty can increase substantially. I think some manufacturers are more conservative than others too, I've pushed it a few times in Mercs and never run out but also learned the hard way not to trust Chevy trucks at least from the mid 2000's.

 

Ya, I've gone under in my wifes 2018 GMC......would've gone alot further, but I don't drive it enough to have that "feel" for how low I can go.

[Frank Brown]

Be careful about always running the fuel so low.  Fuel lubricates and cools the fuel pump.  Running the bike so low all the time stresses the fuel pump and shortens its life............

[Rougarou]

23 minutes ago, Frank Brown said:

Be careful about always running the fuel so low.  Fuel lubricates and cools the fuel pump.  Running the bike so low all the time stresses the fuel pump and shortens its life............

 

RT is at 145k,.....how much shorter fuel pump life can I get?  I'll chance it.

[Hosstage]

I just can't run them that low unless caught out nowhere to get fuel because it gives me heart palpitations.

My wife on the other hand has no problem running her car into the red zone, "plenty of gas to drive to work all week." No.

[Rougarou]

14 minutes ago, Hosstage said:

I just can't run them that low unless caught out nowhere to get fuel because it gives me heart palpitations.

 

 

I think they make pills for that issue

[Twisties]

It's pretty rare on the RTs.  We're still getting used to the reduced range on the GS's.  The one time, as mentioned, both Garmin and the lady at the local coffee shop gave us incorrect info on the distance to the next town.  This time I had forgotten I needed fuel and didn't leave time for it before my appointment.  I was pretty sure I'd make the round trip, but it was definitely closer than I'd like.  Also, I'd point out, that here in the western US there are a number of stretches that will push a GS to it's range limit....  so avoiding a low tank is not always an option.

 

On the RT's when you hit 0 you enter reserve.  1.1 g remaining.  On this GS, IDK about Sharon's yet, when you get the low warning around 50 miles remaining, I probably am entering reserve, or my fuel strip is not properly calibrated.... that's actually what this thread was originally about... asking if it was normal to be nearly out at 0, or if that should start reserve.  This bike would definitely not make it 25 miles past 0 remaining.  The RTs can go 40-60 miles on reserve.

 

I think when I take the bike in for the swing arm recall I'll see if they calibrate the fuel strip for me on warranty.

[Frank Brown]

29 minutes ago, Rougarou said:

 

RT is at 145k,.....how much shorter fuel pump life can I get?  I'll chance it.

My 05 RT had 232,000 on it when I sold it in 2012 and it's still going with the original fuel pump........

[Rougarou]

 

[Hosstage]

The only way to tell for sure how far a tank will go is to bring a gallon with and run it out.

I like my carbed bike that has the old school petcock and reserve, it coughs or dies, I flip it, and off I go. Right to the gas station.

On the EFI bike, the light comes on, and off I go. Right to the gas station. I think the light has come on once in 8 years, the petcock flipped maybe 3 or 4 times in 20 years.

[taylor1]

12 hours ago, Hosstage said:

the petcock flipped maybe 3 or 4 times in 20 years.

I took the airhead out 2 days ago. Didn't even think to look in the tank. Going around 60, 10 miles down the road and the bike starts to die. I'm thinking crap, now what... this is the bike I am planning on taking to Fart. Pulled off the road, flipped the petcocks, gave it a minute to refill the bowls and off to the gas station. Even though not practical, I think every bike should have a manual reserve on, just in case.

[Hosstage]

33 minutes ago, taylor1 said:

I took the airhead out 2 days ago. Didn't even think to look in the tank. Going around 60, 10 miles down the road and the bike starts to die. I'm thinking crap, now what... this is the bike I am planning on taking to Fart. Pulled off the road, flipped the petcocks, gave it a minute to refill the bowls and off to the gas station. Even though not practical, I think every bike should have a manual reserve on, just in case.

I tend to agree, even with EFI.

[Rougarou]

54 minutes ago, taylor1 said:

Even though not practical, I think every bike should have a manual reserve on, just in case.

 

Why,.....cars don't have them and they have those nifty modern conveniences of fuel gauges and idiot lights too.  As much trust is put into them as is the bikes I ride.  I know I can go pretty deep under the fuel gauge of my '89 Chebbie truck, have tempted fate on the wife's GMC (not as comfortable on that one 'cause I don't drive it regularly) and the Subaru has been deep under the E.  I also reset the trip odometer every fill up so I know the average distances I ride/drive. 

 

I dunno why bikes manuals have "usable fuel" even as a listing.  Either it holds xx gallons or it doesn't.  To me, usable fuel is until the bike goes dead, and if it does, it's not the bikes fault, its Kramers fault for making me tempt the gauge.

 

 

 

 

[dirtrider]

1 hour ago, Hosstage said:

I tend to agree, even with EFI.

Morning  Hosstage

 

The problem isn't so much the EFI it is the high pressure fuel pump inside the fuel tank. Unless you have a movable pump pickup (THAT would bring on way more issues than no reserve). Or have a side to side tank crossover hose with a reserve valve in it but that would then require a dual compartmented  tank to be predictable. Or go with dual (selectable) fuel pumps with a compartmented tank. The added problem with any of the above is they would also need a very complicated petcock as the return fuel would also have to be switched to the pumping side.   

 

OR, why not just make it simple & easy,  just  have a low fuel light, when the light comes on start looking for fuel.   

 

The other problem with high a pressure in-tank easily implemented  reserve system is that requires running out-of-fuel before switching to reserve as the rider doesn't know exactly when it needs to switch to reserve. If a rider starts running a high pressure  high flow fuel pump out of fuel a few times that will eventually burn the pump out as the pump needs continuous fuel flow through it to both cool & lubricate it.

 

Some modern BMW fuel injected motorcycles (like my 1200 hexhead) do have a hidden reserve as the right side tank wing never completely empties in normal riding (it can in aggressive riding though). So if/when it quits due to lack of fuel just put your folded  riding coat on the ground  on the L/H side of the motorcycle then softly lay the motorcycle on the L/H side valve cover to transfer the hidden fuel to the L/H side of the tank. It isn't a lot but can get you to a place of safety or even a close filling station.  

[taylor1]

1 hour ago, Rougarou said:

Why,.....cars don't have them

Cars.....motorcycles.... a whole lotta difference in what could happen if you run out of fuel. I agree that if it does happen it's one's own stupid fault. Never wanted to play the game of let's see how far I can go. I have never run out on the RT. Fuel gauge, low fuel light. On the older bikes, no fuel gauge, no low fuel light, it has happened a few times. When it did, I was sure happy that I had that crutch of a reserve. Most times I did not even stop. Just reached down and flipped the cocks. Probably only dropped 15 mph until I was back to speed.

[joeb]

I've had the same questions as my new to me 09 GS has a smaller tank than my RT.

 My low fuel caution light comes on at 50 or 55 miles. This last time I ran it till it said 25 miles to go and I put in 4.8 gallons. That jives with the computed 49mpg. Not sure if there is any fuel left after it reads zero, unless tank actually holds more than 5.3

[Skywagon]

I'm really curious why people run their bikes and cars to critical levels of fuel in the first place.  The last time I actually ran out of fuel was in high school when my Corvair died, and I coasted the 2 blocks home.  Once and only once, I ran my RT until the fuel light came on.  I ran it about another 20 miles just so I would understand normal full range.  DR posted about range earlier.  It's nearly identical to what I do.  I stop for fuel between 250-280 miles.  My one time excursion on low fuel I was at 325 miles when I chickened out going further.

 

I understand if you are off in the dirt, but in populated areas I don't understand why risking an outage and pushing.  It's too darn hot here to run out of fuel.

 

With all the crazy wx we've seen in Texas the last few years, hurricanes, floods, no gas, etc....I keep my cars and bike full.  When it gets to a quarter tank on cars I gas up.  

 

Just curious.

[Hosstage]

4 hours ago, dirtrider said:

Morning  Hosstage

 

The problem isn't so much the EFI it is the high pressure fuel pump inside the fuel tank. Unless you have a movable pump pickup (THAT would bring on way more issues than no reserve). Or have a side to side tank crossover hose with a reserve valve in it but that would then require a dual compartmented  tank to be predictable. Or go with dual (selectable) fuel pumps with a compartmented tank. The added problem with any of the above is they would also need a very complicated petcock as the return fuel would also have to be switched to the pumping side.   

 

OR, why not just make it simple & easy,  just  have a low fuel light, when the light comes on start looking for fuel.   

 

The other problem with high a pressure in-tank easily implemented  reserve system is that requires running out-of-fuel before switching to reserve as the rider doesn't know exactly when it needs to switch to reserve. If a rider starts running a high pressure  high flow fuel pump out of fuel a few times that will eventually burn the pump out as the pump needs continuous fuel flow through it to both cool & lubricate it.

 

Some modern BMW fuel injected motorcycles (like my 1200 hexhead) do have a hidden reserve as the right side tank wing never completely empties in normal riding (it can in aggressive riding though). So if/when it quits due to lack of fuel just put your folded  riding coat on the ground  on the L/H side of the motorcycle then softly lay the motorcycle on the L/H side valve cover to transfer the hidden fuel to the L/H side of the tank. It isn't a lot but can get you to a place of safety or even a close filling station.  

I had forgotten about the fuel pump putting pressure on the system, a petcock probably would not work in that scenario.

 

I also don't understand the need to run so low on fuel when not forced due to lack of access. I keep a close eye on my trip odometer that gets reset each fill, much more so than the actual guage.

[Rougarou]

4 hours ago, taylor1 said:

Cars.....motorcycles.... a whole lotta difference in what could happen if you run out of fuel. I agree that if it does happen it's one's own stupid fault. Never wanted to play the game of let's see how far I can go. I have never run out on the RT. Fuel gauge, low fuel light. On the older bikes, no fuel gauge, no low fuel light, it has happened a few times. When it did, I was sure happy that I had that crutch of a reserve. Most times I did not even stop. Just reached down and flipped the cocks. Probably only dropped 15 mph until I was back to speed.

 

Cars, motorcycles, if you run out of either, what's the difference?  I'm truly lost.

 

45 minutes ago, Skywagon said:

I'm really curious why people run their bikes and cars to critical levels of fuel in the first place. 

 

Me, it's laziness   I'm always in a hurry to get to work, then when it's time to come home, I'm always in a hurry to get home,.... I don't much like stopping during either evolution.

 

In the cars/trucks while traveling (not the around town stuff), when the idiot light comes on, I start looking.  Typically, 'tween here and Sulpur, La, I kinda know where my stops are.

 

45 minutes ago, Skywagon said:

 

 

The last time I actually ran out of fuel was in high school when my Corvair died, and I coasted the 2 blocks home.  Once and only once, I ran my RT until the fuel light came on.  I ran it about another 20 miles just so I would understand normal full range.  DR posted about range earlier.  It's nearly identical to what I do.  I stop for fuel between 250-280 miles.  My one time excursion on low fuel I was at 325 miles when I chickened out going further.

 

I ran out my mom's chebby impala in hi skool,.....that was a funding issue.

 

When I was on recruiting duty, I ran out the govvie car.  Driving from Alexandria to Shreveport, I had meant to fill up in Natchitoches.  The good metal radio station from Shreveport tunes in just south of Natchitoches, so I tuned it in,.....passed Natchitoches and when I noticed, it was too late.  Ended up making it close to Shreveport, like exit ramp close.  Called another recruiter in the Shreveport office to come get me,....problem solved.  Daydreaming/jamming caused that mishap

 

45 minutes ago, Skywagon said:

 

I understand if you are off in the dirt, but in populated areas I don't understand why risking an outage and pushing.  It's too darn hot here to run out of fuel.

 

With all the crazy wx we've seen in Texas the last few years, hurricanes, floods, no gas, etc....I keep my cars and bike full.  When it gets to a quarter tank on cars I gas up.  

 

Just curious.

 

Heat, cold, rain, it's no biggie.  Waited near three hours in the cold for my wife to come get me at my last laydown and you know I kinda enjoy the heat.

 

Suck it up buttercup.

[taylor1]

11 minutes ago, Rougarou said:

 

Cars, motorcycles, if you run out of either, what's the difference?  I'm truly lost.

I guess sometimes things just can't be explained. Kinda like when mom used to tell me not to play out in traffic       

[Skywagon]

Roug… you should have stopped in Natchitoches and had a few meat pies and got gas. As far as heat, I can take, I just don’t like it. When you get to be my age… I don’t do sheet I don’t like. I don’t paint, mow, hunt, wax my car, work, or loan money. I can do all those things, but I don’t like it and I’ve earned the right not to. 
 

Spent a lot of time on road crew on top of black top in the summer months growing up… taking it vs liking it. 
 

If they still had full serve gas stations, I wouldn’t gas my car because….wait for it… I don’t like it. That said I would never let someone gas my (former) plane even if it was raining

 

[Rougarou]

1 hour ago, Skywagon said:

Roug… you should have stopped in Natchitoches and had a few meat pies and got gas. As far as heat, I can take, I just don’t like it. When you get to be my age… I don’t do sheet I don’t like. I don’t paint, mow, hunt, wax my car, work, or loan money. I can do all those things, but I don’t like it and I’ve earned the right not to. 
 

Spent a lot of time on road crew on top of black top in the summer months growing up… taking it vs liking it. 
 

If they still had full serve gas stations, I wouldn’t gas my car because….wait for it… I don’t like it. That said I would never let someone gas my (former) plane even if it was raining

 

 

I've had the meat pies a'plenty.  My little brother graduated from the Louisiana School for Math Science and the Arts, as did my nephew.  Only 200 junior hi skoolers get in that place each year.   Anyway, I can not do all those things that you don't like to do, but,.....I sorta like cutting my grass, painting, filling my own tank (I don't hunt, wax my vehicle(hell, don't even wash them), or loan money).  But being outside, sweating (the good gooey sweat), laboring, making sawdust, putting things together, building, creating, beats being inside any day of the week,....I can't have an unproductive weekend/timeoff---relaxing to me is actually working 'round the house.  I can pay someone to do all that, but, meh, nope, I'd rather do it myself, 'cause it'll get done to my liking or tools get thrown.

 

You need to move to Jersey or Oregon to have someone fill your tank,......and, you'd escape the Houston heat that you so despise

 

Anyway, I'm pretty regular about getting under zero before I fill up either bike, I've not gone empty yet, but certain I've been on vapours many times.  If I run empty, I got a good wife that will grab a can and meet me where ever I'm out.

[Rougarou]

So this morning, I hop on the GS to go to work, notice while rolling out the garage, the bike felt sluggish,.......look down, back tire is flat and I just plugged it Sunday.  So, I back it back in the garage and hop in the Subaru.  This what the miles to empty looked like about twenty miles before fill-up:

 

Subaru fuel tank is 18.5,....my fill up, 18.3,.....I had .2 left to go  So if you do the math, you know the "computer" is off.