Fuel light + computer?!

jomo · Post by **jomo** » Tue Sep 11, 2007 2:20 am

Hi,

I'm fully enjoying my new (to med) R1200R, but I do have some questions I hope you guys can answer:

- The computer isn't very reliable, is it!? It tells med I can go another 100 miles just before get som gas and fill it up by 90 percent...

- Is there actually a fuel light as well on the bike even though i have the computer option? If yes, any reports on it failing?!

Thanks,

Johan

hass · Post by **hass** » Tue Sep 11, 2007 2:49 am

The fuel is measured using reed switches - not very accurate but better than nothing.

Yes there is a yellow low fuel warning light.

Post by **Caroanbill** » Tue Sep 11, 2007 2:59 am

.. but both must run off the same fuel level sensor, because both guage and fuel warning light show empty since the sensor failed on my bike. Oh, and no distance to empty either, of course.

Moral .. use your trip meter like you've probably always done - take a full tank and reset when you fill. That's been my only fuel guage for the last 4,500 km (all done in a week

) .

I'm waiting on a new sensor from Germany: no spares held in Australia.

Phillo · Post by **Phillo** » Tue Sep 11, 2007 5:53 am

My computer seems to be fine, I have never run out of fuel and as an example this morning with the computer showing 55 km's to go I stopped and filled up 17.36 litres to the bottom of the red filler neck which I do on a regular the tank taking anything from 16 to the maximum I have had it take 18 litres

Post by **deilenberger** » Tue Sep 11, 2007 9:10 am

hass wrote:The fuel is measured using reed switches - not very accurate but better than nothing.

Where did you hear this?

AFAIK - the fuel level is measured using a resistive temperture sensing strip - which gives a continuously variable output - varying depending on where it detects a temperature difference between the fuel and the air above it... it's similar in principle to the one BMW tried many decades ago on the original K bikes - which worked well in the lab and totally bombed in use on the bikes.

Yes there is a yellow low fuel warning light.

Yes there is - and if the fuel level system isn't working correctly - it's time for a visit to the dealer. They may have to replace the sensor strip, or they may just have to calibrate it.

Calibration is done by emptying the tank of all fuel and letting the system normalize for some time. They then put the amount of fuel into the tank that you want the light to come on at - and using the GT1 - set the turn-on point.

Mine is very accurate. Went ~235 miles on Sunday - the fuel remaining readout indicated I had ~28 miles remaining. It had turned on at about 45 miles (I assume one gallon since the MPG readout was about 45MPG when it turned on..) When I filled the bike - to a bit up the orange tube in the filler - it took 5.2 gallons. This was actually the first time I'd ran it far enough to have the fuel light illuminate..

FWIW - I'm riding a black w/white stripes bike because the Granite one I originally was going to buy had the same sort of sensor problem. On a final "acceptance" test ride I took on it - with the fuel readout indicating about 1/2 tank, and 144 miles remaining - it ran out of fuel. I should have noticed (duh!) that it had indicated 144 miles remaining for about 15 miles - but was enjoying it too much for it to really register.

Post by **ka5ysy** » Tue Sep 11, 2007 9:00 pm

Happily my fuel gauge is highly accurate. I have taken the tank down to 8 miles showing on the computer and put 5.5 gallons in the tank. The low fuel light comes on about 40 miles.

As suggested, I reset both trip odometers and use trip II for the tank milage. I am getting around 250 miles per tank now with the 10 mile display on the computer.

I LOVE THIS BIKE