Fuel Guage Errors

[Bear of Kent]

Hi Everybody

 

I wonder if you could all help me with an issue that I have with BMW over my erratic fuel reader.

 

When I fill up the mileage remaining starts to read at around 120-130 miles and this rises quickly over the next 30 miles to a maximum of 196 miles. It then stalls briefly and starts to come down. It doesn't really start to give an accurate reading until the last 50 miles. The Fuel Bar on the other hand goes straight to full when the tank is filled but stays on full for nearly 100 miles before starting to fall.

 

I have never seen over 196 miles registered as fuel remaining.

 

Is this normal?

 

Please let me know, I need ammunition to go back to my dealer who is suggesting at the moment that "they all do that".

 

Thanks

[lkraus]

I'm not sure which bike you are talking about, but your profile shows a R1200RT, which year? The fuel readouts on the R1200RT are neither precise, accurate or reliable.

 

They can be improved by resetting the average mpg readout to zero at each fillup. Doing this, my bike computer indicates that I typically average about 49mpg, and have 300-320 miles per tank. I use the trip meter (also reset at each fillup) as my gauge and start looking for gas at about 250 miles. Generally takes around 5 gallons.

 

The rise and gradual decline in miles to empty is typical, "they all do that". Don't count on an accurate reading in the last 50 miles. I have run as much as 30 miles after "empty" without problems, but the prediction could easily have been wrong in the other direction, leaving me stranded.

 

A prediction of less than 200 miles per tank is unusually low for an RT. If resetting the mpg display does not improve the prediction, I'd be talking to the dealer again, especially if you are under warranty.

[Bear of Kent]

Hi Larry

 

It's a 2011 R1200RT so it has the new fuel reader system and not the old strip which caused mucho problems for a lot of people though I never suffered.

 

I know the readings aren't gospel but I was always happy enough with my GS and both my old and new K12GTs.

 

The readings I am consistently getting from my RT suggest to me that however the new system works it is not seeing the top third of the tank.

 

I am hoping that owners of the 2010+ model will come back and say they always see starting mileages of around 300 as soon as the tank is filled. I can then take this to BMW and get them to take this seriously.

 

Thanks

[tsp]

The 2011 has the fuel strip. I suggest you take it to the dealer and at least get it calibrated. Replacement is a better option.

My 2010 RT always shows a range of 325 to 340 miles after a fill up. It's adjusted after that based on your MPG average. I reset my mpg and mph at each fill up.

 

Btw, my fuel strip had to be replaced once.

 

tsp

My MC blog

[BrianM]

2011 should have a float. Production beginning August 2010 appears to be the change to a float.

 

I don't have the computer, so can't comment on the accuracy.

[Danny caddyshack Noonan]

My range has never shown better than 240 or so. It will, sometimes, park on the upper reading for awhile though the LED strip will always show consumption segment by segment. The only time I've gotten more than 44mpg is with a strong tailwind on I5 a few weeks back (47mpg). Got 38mpg coming back into it the next day so, it all balanced out.

[Guest Kakugo]

I had similar problems. I reset the mileage calculator a couple of times and now it seems to be pretty accurate.

 

Apparently (take it with due caution) on some bikes if you don't reset it once in a while it will start this sort of erratic behavior. Don't ask why.

[HeliMark]

I have a 2012, and it will usually go to 260 miles remaining. But by the time I get to around 250 when I fuel up, it says I have 90 miles left. I just chalk it up to "it is what it is". I know it looks at the current mpg, which depending on how you were just riding will give a wide range. I depend on the trip mileage I reset every fill up. Safer that way, although it is better then my Harley....

 

Mark

[Hank in WV]

My 2010 RT shows about 330 miles at fill-up.

[bikebits]

2011 should have a float. Production beginning August 2010 appears to be the change to a float.

 

Correct.

[David R]

I have a 2012 R1200R with a slightly smaller tank. It works just like yours.

 

Fill up, 260 miles to go. It takes a while to think that one out.

 

It stays on full until about 100 miles on the trip meter then starts to read lower.

 

The closer to empty the more accurate the gauge is and so is the miles to go.

 

I don't want to mess with mine. Its working. I can predict what I have by the trip meter and the gauge says

"I have some gas" is good enough.

 

My bike still has a fuel strip. I can see it in the tank.

 

David

[Bear of Kent]

Hi Everybody

 

It is a float system and not a strip reader.

 

I almost never reset my mpg and mileage counters so I will try this for starters.

 

My only concern is that while the readings are all wrong they have been consistently like this for over a year and 14,000 miles.

 

Lets see...

 

 

[Bear of Kent]

Hey Danny Caddyshack Noonan

 

Just noticed your mpg figures. I'm impressed! You must be wringing that machine dry to only get 38mpg. Either that or you've got a leak.

 

I fight my way right across London every morning and then blast around the M25 at 100+ to get home and I still get 46mpg.

 

And I thought you guys had blanket 55mph speed limits in force. Obviously not )

[Boffin]

Hey Danny Caddyshack Noonan

 

Just noticed your mpg figures. I'm impressed! You must be wringing that machine dry to only get 38mpg. Either that or you've got a leak.

 

I fight my way right across London every morning and then blast around the M25 at 100+ to get home and I still get 46mpg.

 

And I thought you guys had blanket 55mph speed limits in force. Obviously not )

 

Don't forget that the Americans don't have real gallons. Ours are 20% larger than thiers. It comes from thier undersized pints - 16 fluid ounces as opposed to a real pint of 20 fluid ounces.

 

 

Andy

[kgerry]

i thought i read that the fuel gauge reads to reserve, then resets?

 

when i fill my 2013 it reads to about 350-380 kms.... which would be almost exactly where my "reserve" portion would kick in (1 gallon/5 litres)

[dirtrider]

Evening Bear of Kent

 

Pretty well all of my hexheads have done that. Your onboard computer is using miles traveled vs the fuel sender reading so right after you fill up & start the engine you are getting 0 miles per gallon. If you sit at the pump with the engine running for a few seconds that makes it worse. Then if you sit waiting to exit the gas station it goes even lower. Then if you hit a stop light right after exiting the gas station it gets even worse.

 

It takes a while for the miles traveled to catch up with the fuel ACTUALLY used to get a decent (accurate) fuel mileage average.

 

Or put another way-- could you ACCURATELY figure fuel mileage with a just a full tank & a bit of engine running with only a mile or two traveled? (yep, neither can your onboard computer)

 

[Bear of Kent]

Ha ha...

 

That puts Caddyshack back in with the mortals at about 45.6 Sterling Miles Per Gallon (SMPG). I has been wondering just what you would have to do with an RT to drop down to 38 SMPG.

 

I get the fact that the reader will be a bit erratic to start with due to lack of data but it should at least start with the real range travelled from the previous complete fill up.

 

I can even think of exactly how I would write the code to stop the reader using just real data until a sufficient amount had accumulated for a good estimate, say 30 miles. Before that it could rely solely on actual miles travelled compared with the average consumption over say the last 600 miles. This could even be pre-programmed for new bikes so they don't go haywire with no data at all. You could even phase this in over the first 50 miles travelled so it doesn't jump suddenly.

 

Anyway, I will need to fill the tank on the way home tonight so I am going to zero everything just before I switch off to fill and see what happens when I start up again.

[GRB60]

My 2011, which has a float, usually settles on a range around 280 miles. It is normal for the bar indicators to go straight to full and the miles to empty to lag, since it is a calculation based on how you are riding rather than available fuel.

 

At the low end of the tank the miles to empty purposely misleads you to "hide" the 1 gallon reserve. In actuality the reading is miles to reserve. Considering that, mine is pretty accurate.

[kgerry]

isn't that what i said?? ha ha

[Bear of Kent]

Thanks GRB60

 

That's exactly the answer I need to take back to my dealer and direct to BMW UK customer service.

 

Starting with a reading of 120 and never rising above 200 is definitely a fault and I am going to throw all my toys out of the pram until they admit to it and fix it!