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Fuel Reserve (1 US gal)?

A

AdventureGoat

Guest
The standard GS and the GSA has an advertised fuel reserve of 1 US gallon.

Is one to assume that when the Fuel warning light comes ON, that you now are in this reserve fuel? Or is there a lower warning limit?

I guess the old days, of reaching under the tank and switching the petcock over to "Reserve" are gone... :confused:
 
My understanding is that when the RANGE indication reads zero, you have one gallon left. At least that seems to work for me.
 
The other day i put gas in when I had 12 miles (indicated) left

I put in almost 6 gallons - which theoretically leaves 1.1ish gallons (Have an RT)

YMMV
 
As I understand it,

The calibration for this is based on the design spec not the real life bike you are riding. I donÔÇÖt remember the DNS spec BMW uses so only for example if the design is based on a 6 gallon design and the DNS spec defines fuel capacity as 80% of that capacity and reserve as the rest you would have a 4.8 gallon main with 1.2 gallon reserve.

The real tank may be larger or smaller fractionally resulting in different mileage.

The DNS spec comes in play because of the various certifications a bike design goes through in having things such as GVWR and payloads set to gain certification. Because of the difference in what a full tank is from one person filling to the next they use a calculation rather than actual weight. Dry weight of a bike can be weighed on a scale the wet weight is done mathematically for these purposes rather than by adding fluids.

In turn the calculationÔÇÖs fuel loads are used to calibrate the electronics monitoring fuel load.
 
My understanding is that when the RANGE indication reads zero, you have one gallon left. At least that seems to work for me.

Not on my '05 GS without the computer where the "range" function is the "miles left to no gas" display that comes on when you have about 1.1 (not 1) gallon in the tank.

My tank holds 5.2 or 5.3 gallons, forget which. If I wait until the "miles left to zero" reads about 20 miles I can put in about 4.6-4.7 gallons if I really try. That fits with about 1/2 gallon left which matches the around 20 miles range. My usual mileage is in the low 40s/gallon.

Now, if I stuck the gas nozzle in the tank and thought the tank was full when it clicked off automatically then I might believe I've got extra gas. Not so. I can easily add 0.6 ~ 0.7 gallons to the tank after the automatic shutdown without coming close to overfilling the tank.

// marc
 
08 RT here. If i take it to 0, I can only get in about 5.5 gallons, which means I still have about 1.7 gallons left.

There was an older post about how to have this thing recalibrated if you're real anal about it. It doesn't bother me too much.
 
The days of the petcock reserve left when fuel injection arrived, you can't let the injectors run dry. My '08 GS shows a fuel warning light when I have burned about 3 gal. At the end of 4 gal, it shows zero, but I still have over a gal left. It is obviously in error and very annoying to have a fuel warning flashing for almost half the time I ride the bike. The dealer says it is no easy fix. The fuel level they say is read from a strip on the inside sidewall of the fuel tank. They claim more new bikes are wrong than right.
 
The days of the petcock reserve left when fuel injection arrived, you can't let the injectors run dry. My '08 GS shows a fuel warning light when I have burned about 3 gal. At the end of 4 gal, it shows zero, but I still have over a gal left. It is obviously in error and very annoying to have a fuel warning flashing for almost half the time I ride the bike. The dealer says it is no easy fix. The fuel level they say is read from a strip on the inside sidewall of the fuel tank. They claim more new bikes are wrong than right.


....yet it still can and SHOULD be corrected by the Dealer. This "Ain't No Easy Fix" by the Dealer is BS.....
Many new bike owners reported the same issues about fuel sending instruments being off calculation.
Scuttle butt on ADV Rider, report that the Fuel Sender information is corrected by computer software adjustments. You need to do a search on that site for more info.
On my personal '07Adv,the fuel sending instrument works excellant. At the onset of yellow warning light and mileage countdown,I have almost exactly 1 gal of fuel left in tank.
Maybe I'm just lucky.....:brow
 
My 08 RT, when ridden down to 0 miles takes approximately 5.5 gallons. I am really not too worried about what someone else's reads, as long as my reading is consistant. I just plan accordingly.

Heck I am ready for a leg stretch after 250 miles anyway!
 
The other day i put gas in when I had 12 miles (indicated) left

I put in almost 6 gallons - which theoretically leaves 1.1ish gallons (Have an RT)

YMMV

I have run my 05 RT down to zero a number of times and have put in 6.6 to 6.8 gallons. At zero miles you have some fuel left but, I would not count on having a gallon.
 
My understanding is that when the RANGE indication reads zero, you have one gallon left. At least that seems to work for me.


THIS IS NOT TRUE at least on my 09 R12RT. I went exactly 4 miles past 0 and killed my bike on the freeway.

to assume that when you fill up at the 0 point with 6 gallons gas so there is one gallon left is false presumptive logic... i used to think the same thing too.

instead, after I ran it out of gas I filled it to where I thought full was before (about 6.2 gallons). then I very slowly began to add additional gas (hard to do because it wanted to splash out) but was able to add almost another gallon to 6.9 before I figured that was enough.

Also keep in mind the fuel strip is less than perfect, and many have had it replaced for false indications...

the best is to use your odometer and trend data... if you get 40mpg, you are going to get get 280miles plain and simple. Ever since running out I refill pretty soon after the light comes on, and dont run it to 0 anymore.

just my $.02
 
GSA holds 9;

Ask me how I know? I've put it in:). Thats close to pushing! My light and computer are quite accurate and if I get to zero bars on the gas gauge, I'm in danger of walking. I get down to 30-50 miles frequently left, according to my computer and almost always use 8+ gallons. 38-45 mpg, depending on my wrist. Randy:thumb :usa
 
THIS IS NOT TRUE at least on my 09 R12RT. I went exactly 4 miles past 0 and killed my bike on the freeway.

I think someone mentioned on this thread or another one like it, recently, that the '09 RTs went away from the fuel strip and back to a more conventional float system. Perhaps this'll be more accurate in the long run. I have an '09 as well, and haven't verified exactly what's in my tank, but I don't have the desire to find out the hard way. I'm taking the fuel light at its word and am not pushing it to the limits. :scratch
 
Want to know!

Put a gallon in the "trunk" and run her out of gas, then you'll know more:thumb . Small gallon gas can are easy to carry back there, for research purposes here:). Randy
 
Amen Polarbear

I did a functional test on my '07 RT. Took the plastic plug out of the filler cap and brought the fuel up to the metal tab. Low fuel light usually comes on about 45 miles to empty.

During my functional test I went 53 miles past 0 to empty (about 1 gallon). Filling it up the pump indicated 7.09 gallons. If I remember correctly I was getting between 45 and 50 mpg.

Of course B1pilot burning 100,000 lb/hr in full burner, you gots to know your limitation. No pulling over when you run out of gas in enemy airspace!
 
I believe the way it's supposed to work is that the low fuel warning (yellow triangle and flashing pump icon) comes on when you reach the reserve fuel level. It then counts down the miles until empty (theoretically, that is). The low fuel warning came on far too early on my bike ('06 RT) and my dealer re-calibrated it. This was/is a common complaint. Re-calibration involved the dealer emptying the tank, allowing the fuel sensor strip to dry, pouring in a measured quantity of fuel (the reserve quantity) then plugging the bike into the shop computer and performing some kind of magic. It has worked pretty well ever since. Your dealer is exaggerating. Get it fixed; you paid for it and your bike's under warranty. Some have had to have the fuel sensor strip replaced.
 
My sensor strip was replaced under warranty last year not for inaccuracy, but for total failure. The new strip reads just like the old one, and I can go a ways after the zero reading.

B1: I would not assume that an RT and a GS read the same. Different tanks, and probably different software.
 
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