'07 RT Gas Tank Volume?

The fuel gauge on the RT can be recalibrated by the dealer. It goes something like this: first, they have to empty the tank (so don't go in with a full tank); then they must let the fuel sensing strip in the tank dry; then they pour back in a measured quantity of gas -- whatever you want the reserve to be; finally, they hook up the bike to the diagnostic computer and "instruct" the bike to use this new fuel level as the reserve amount. I, and many other R12RT owners, have had this done under warranty.

Not to resurrect a dead horse, but...

marcopolo said:

... they hook up the bike to the diagnostic computer and "instruct" the bike to use this new fuel level as the reserve amount. I, and many other R12RT owners, have had this done under warranty.

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I will have my dealer go through this procedure at my next service (should be later this week); will be interesting to see what happens. I went out last week-end, and took along a 1 gal gas container - just in case my 'intuition' should prove wrong .

Ran the bike ('07 R1200GS) past the "---- RANGE" mark for 32 miles. Stopped at a gas station to refuel. GPS showed 236 trip miles, and I put 4.759 gal in. OBC showed 49mpg, I calculated 49.59mpg. That left me with around 0.5 gal in the tank, for a real "Till Empty Range" of almost 263 miles.

donelson said:

I tried to "test" my '07 RT tank volume the other day. Got to my home town with 6 miles to empty (as stated by the computer) so I chickened out and filled up. All I could cram into the tank was 5 gallons. The manual states 7 gallon tank. I figure there's bound to be some air space that's unusuable, but 2 gallons? I drove 40 miles after the warning light came on.

Or is the computer that poorly calibrated. I gotta believe the Germans are better than that.

Any real life experiences as to tank volume?

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I was crossing farm country this past Sunday in a rainstorm and saw I had 17 miles of fuel left on display,light had come on at 50... hit the GPS for fuel options...16.5 to fuel..YIKES... I pulled into station after easing up to "conserve" fuel and arrived with 1 showing on display. I topped off as usual and only got 6.1 gallons in the tank...guess I could have gone another 50 miles or so. Still not sure of my limit...but did not feel good not knowing true range

I wish...

I rarely make it to "empty". The SO's R1200CL has a tiny tank so every time we stop for fuel, I top off. I do get better economy on the RT - 12 liters for her, 10 for me... Having said that, the most I've ever squeezed in to the tank was 22 liters, or about 80% full. Everyone says I should run it out, but I hate doing that to an injected vehicle.

All this discourse about a topic that is so easy to resolve logically and empirically.
1. The tank holds 7.2 gallons just as BMW states!
2. The "miles remaining" readout is an estimate based on fuel consumption rate since last reset, but it is an estimate to a reserve remaining quantity that varies marginally from bike to bike due to calibration differences, and varies very slightly from tank to tank within a bike due to the "sloshing factor".
3. Accordingly, to the "miles remaining", you must add some number of miles based on your recent fuel consumption rate and the "typical" quantity of fuel remaining in your tank on your bike given the status of your BC's calibration.
4. The best way to determine the actual miles remaining when your BC states "0" is to simply run the bike dry, under "average driving conditions" while carrying a small quantity of fuel in a gas can. Do this a couple of times to get an average. It won't hurt your bike to run out of fuel!
5. Obviously the total miles you get from a tank will vary depending how full you fill the tank. Sure you can cram more fuel in by removing components BMW designed into the fuel system for safety, but for most of us, the real issue comes into play only when needing to stretch for that next gas station during the final 50 miles or so of capacity.

Dealer cannot calibrate

zarinelli said:

I will have my dealer go through this procedure at my next service (should be later this week); will be interesting to see what happens.

[...]

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Asked dealer to perform the procedure above. Mechanic claimed he couldn't find an option to reset the "RESERVE" in the software, so they didn't do it.

Anybody here know what the setting is called to reset the RESERVE in the software?

Hmmm...

maxfrankel said:

[...]
5. [...] Sure you can cram more fuel in by removing components BMW designed into the fuel system for safety, but for most of us, the real issue comes into play only when needing to stretch for that next gas station during the final 50 miles or so of capacity.

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Interesting conjecture...

On my bike, when the contraption was in there, the last segment on my fuel gauge never came on - almost as if the tank didn't get filled all the way. No change in when the reserve light came on, though. After removing the thing, the last segment on the fuel gauge comes on every time I fill the tank. Already had this removed on my 05 and never had any 'safety' issues...

One more thing

I've had similar "fibs" from "miles to empty" on my '07 RT and my F800ST. Ran the F down to zero, assumed that it would start sputtering immediately but was able to run another 5 miles or so to gas up, still don't know how much I had left in the tank.

Back to the RT, a couple nights ago I'm going to gas it up and I put it on the center stand, as usual. I fuel up to the point that the pump kicks off, then do a couple short squeezes and again both times the pump shuts off. Full, right?
Back on the road and the computer takes it's usual few seconds to calculate the fuel in the tank. The display reads just below full. This perplexes me as this is not the first time this has occured.

Have you had a similar experience? Not that it's all that critical, just mildly annoying.

(Oh sheesh, just read some previous posts and I think I understand now, sorry)

Yep...

... very similar. The funny thing is that my OBC's mpg is dead on (checked manually, using GPS data to compare), so I look at my average mpg's and do a quick calculation to see actual DTE - and essentially ignore the whole RANGE display.

Works pretty well - but yes, on an $18,000+ bike, you'd expect the fuel gauge to work correctly. Annoying is the right term. On the other hand, that's my only beef with the bike, so I think I can be happy, overall

wezul said:

I've had similar "fibs" from "miles to empty" on my '07 RT and my F800ST. Ran the F down to zero, assumed that it would start sputtering immediately but was able to run another 5 miles or so to gas up, still don't know how much I had left in the tank.

Back to the RT, a couple nights ago I'm going to gas it up and I put it on the center stand, as usual. I fuel up to the point that the pump kicks off, then do a couple short squeezes and again both times the pump shuts off. Full, right?
Back on the road and the computer takes it's usual few seconds to calculate the fuel in the tank. The display reads just below full. This perplexes me as this is not the first time this has occured.

Have you had a similar experience? Not that it's all that critical, just mildly annoying.

(Oh sheesh, just read some previous posts and I think I understand now, sorry)

Click to expand...

maxfrankel said:

All this discourse about a topic that is so easy to resolve logically and empirically.

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Mr. Spock would not think the computer that miscalculates miles to empty logical, nor shoud the Germans. I, quite frankly, am mildly disappointed with the OBC in an era where we can cure spark knock in milliseconds, but can't link a mass flow and level gauge.

The OBC is dead on (at least to my error level and comfort factor) when it comes to calculating the gas mileage. Why can't the level be linked and recalculated. What's that take? A Cray supercomputer?

Now that would be "quite logical."

donelson said:

Mr. Spock would not think the computer that miscalculates miles to empty logical, nor shoud the Germans. I, quite frankly, am mildly disappointed with the OBC in an era where we can cure spark knock in milliseconds, but can't link a mass flow and level gauge.

The OBC is dead on (at least to my error level and comfort factor) when it comes to calculating the gas mileage. Why can't the level be linked and recalculated. What's that take? A Cray supercomputer?

Now that would be "quite logical."

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It seems to me that the problem is just calibration.

Ran my 06 RT to 5 miles and filled up, still have rubber stopper in and rocked the bike a little got 6.35 gallons in so I don't consider that too bad, gives me a range of about 250 miles. by that time I'm ready to stretch my legs.

100394 said:

Ran my 06 RT to 5 miles and filled up, still have rubber stopper in and rocked the bike a little got 6.35 gallons in so I don't consider that too bad, gives me a range of about 250 miles. by that time I'm ready to stretch my legs.

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Which means you really should have approx. .8 gallons left and enough gas to go another 40 miles.

newfangled gizmos

I do like the BC, but the fuel level indicator on my newish R12RT is quite the pessimist. Mine shows empty after about 5.5 gal. and is in line with others experience here.

I plan to do exactly nothing about it and use the old trip meter method - after all, that has worked well for me since the early Silurian era....

What I like best about the whole BC thing is the temp reading anyway.

Sillurian Period

Gas gauges, low gas lights and odometer readings. . .remember the Silurian Period times way back when we didn't even have a reset on our odometer and we had to look in the gas tank and shake the bike to see how much gas we had. Now we are complaining that our computer on the RT is not in perfect harmony with the total volume of the gas tank. . . man have we come a long way or are we getting so spoiled with technology that everything has to work perfect to our satisfaction or you take it to the shop. I guys I think every bike has little differences, get use to them and enjoy. The digital gas gauge is great, the distance to empty (or reserve) is great and then the flashing ! and little gas pump is cool. . .come on guys mellow out and realize how far we have come in 48 years of riding . . . Ducatic 250 Monza's rule!

Gpodzo
R1200RT
R1150GS
XR650L

Now if I could only get used to my Windows crashing.....

My fuel gage was useless until the 600-mile service, when I had them recalibrate it. When they returned the bike, there was under 2 gallons in it, so I decided to see what the ultimate capacity of the tank really is. I put a gallon in a can into the top case and then rode the bike empty. As good luck would have it, it sputtered and killed while idling at a stop sign across a quiet intersection from a gas station. I pushed it over to a pump, put it on the center stand, popped the rubber sleeve out of the filler neck, and filled it to the bottom of the metal sleeve. It took 7.48 gallons.

The Miles-To-Empty value is still not accurate enough to be of any use. However, the bar-graph fuel indicator is fairly reliable now. When the very last pixel at the bottom of the bar disappears, there's about 0.7 gallon left in the tank. I consider this to be my "reserve", and the MTE is long past 0 miles at this point. The yellow triangle comes on with about 1.5 gallons remaining. I really wish I could swap that MTE readout for a numerical oil temperature value...