R12RTW fuel range test

[mneblett]

Took a gallon of gas with me and ran the bike dry. Sputtered at almost exactly 20 miles beyond "0." Of course, YMMV

 

Nice that unlike previous BMWs (at least the ones i've owned), the miles remaining didn't turn to "---" below 10 miles, but kept counting down to zero.

 

FWIW, the last 20 miles I slowed from 70-71 to 65, then 60. Mileage when from mid-upper 40's to mid-upper 50's -- didn't think I was ever gonna run it out!

[realshelby]

On my recent trip I done some riding in the North Carolina mountains. 309 miles and the range said 38 more miles left! Took just over 6 gallons on that fill up. Manually calculated that was between 50 and 51 mpg.

 

But, to be honest, I have modified the filler neck with a breather hole near the top to squeeze in a bit more fuel when filling. Which I don't care about around locally, but I like the range when eating miles on road trips......

 

Don't squeeze all the fuel in these you can if the bike isn't being ridden enough to burn the level down some right away. Engine heat can expand the fuel.......

[mneblett]

Engine heat can expand the fuel.......

Or fuel can get sucked into the charcoal canister, causing the charcoal to turn into a slurry and block the tank vent. That can cause engine stalling and/or tank collapse.

[RSH]

Did you leave with a full tank or did you just test the lower limit?

 

Curious how far a topped off tank will last on average.

[narcosis]

You're bold Mark. I ran mine down to 22 miles remaining on the display. It took 6.086 gallons to top it off so I probably had another 25 miles I could have went. Good to know that the miles remaining is pretty accurate.

 

Ken

[mneblett]

Did you leave with a full tank or did you just test the lower limit?

 

Curious how far a topped off tank will last on average.

 

Started at a low level; just wanted to know how far past "0" it would go -- 20 miles beyond 0 is a good-to-know number.

 

On refill, I found the manual's listing of 6.6 "useable" gallons to be spot on. Note: that is 6.6 gal. usable from full to sputtering to a stop, not 6.6 gal from full to "0" on the range computer. My bike appears to have ~0.4 gal. still present when "0" is reached.

 

Knowing the 6.6 gal. is accurate, range is a matter of your personal driving habits -- at 70+, (*very* roughly) figure 280-300 mi.; at 60, 350 mi., etc. Pretty straightforward once you have an accurate usable fuel number.

[blackyam]

Hi, everyone. Many years ago the fuel pump on our Taurus car failed. The mechanic told us that it was probably because we ran the fuel low too often. Is there any danger of our doing that on our RTs (in particular, on my 2010 R1200RT)? Thanks.

 

---John.

[mneblett]

Hi, everyone. Many years ago the fuel pump on our Taurus car failed. The mechanic told us that it was probably because we ran the fuel low too often. Is there any danger of our doing that on our RTs (in particular, on my 2010 R1200RT)?

Yes. The BMW fuel pumps are like any other -- their electric motors generate heat and they are cooled by the fuel they pump through their bodies.

 

Run them dry for extended periods, or run them enough times at such a low tank level that the fuel being recirculated gets hot and then cannot adequately cool the pump, and the pump can be damaged by excessive heat.

 

In other words, don't be afraid to go down to the reserve fuel light, but don't make it a habit to take your remaining range down to zero miles.

[blackyam]

Dear Mark, Thanks for the advice. That's very reassuring. I have run down to the low fuel light several times, but I have not yet run dry. I will continue to be careful.

 

---John.

[Skywagon]

I get between 48 and 52mpg as measured the old fashion way. I was in Arkansas last week and was able to buy non-ethanol gas almost everywhere. Mileage increased about 5 mpg average.