Fuel meter
 

Greetings from Cairo

My fuel meter has worked relatively well so far but now, all of a sudden the bars are dropping down twice as fast compared to what it used to be. And there's nothing wrong with the fuel consumption.

Has anyone else had this problem and if so, what was the reason?

And one more thing: If I stop the bike at let it stay put for some time, the bars in the fuel meter will rise back to normal, until I start riding again and then they drop down again almost immediately.

Jami

Mine was the same, I think the only thing it's good at is telling you when it's full and when it's empty . The rest varies as the fuel moves around or seems to. Ps the flashing empty alert and reserve fuel trip always was spot on on mine though never ran dry and most I dared on the fuel trip was 30miles and in got 23litres in .

wow you must have really leathered it Mac! i usually get 50+ from reserve, and on the two occasions that i've...err, 'tested' the reserve limit (ran out) i've had approx. 75 miles from reserve and only then have i managed to get 24L in!

Jami- yes, i agree with Mac-cos about the gauge, mine too is good at showing full and empty and not much in between. I usually ignore it and use the trip meter as a better guide, or just wait for the F-trip to come on. The fuel reserve on this bike is 7L so plenty of time to find a fuel stop f you're on a normal ride. I know its annoying that the gauge isn't much good, i think its because of the shape of the tank.

pete.

Hey Jami. Could it be the heat that is causing the issue?

Mine seems to have got worse lately in exactly the same way...as you say, dropping down quickly while riding, then 'recovering' while parked up.

Even does it overnight, so it's not due to the fuel expanding when hot. Quite the opposite it seems.

I'd trust Osama Bin Laden before I trust my fuel gauge....

I can't agree with the others though, the only time it's right is when the bike is full!

I too have managed 70 miles on the F-Trip, but I use the trip like everyone else. I also fill her up at 150miles, normally get around �15 in the bike, depending on my riding, price of fuel and temp (always get more mpg in the cold).

With a quiet frugel ride (is that how you spell frugle/frugel/fruggle/slow!) I have managed 300 on a full tank, with some fumes to spare, moreover though around 250 is about right.

It's not just the Tenere, my XJR has a crap gauge too.......

Sometimes erratic fuel gauges can be due to a different petrols (particularly with low quality stuff) which doesn't have, or has less anti-frothing agents in it. What happens is the fuel froths up in the tank when you ride causing the float in the tank sender to send false readings to the gauge, when you stop the frothing subsides and everything goes back to normal. Tends to happen in the developing world more than in the west (but it still happens) as our stuff has more additives to stop this kind of thing.

Hey this could be it. I noticed this thing in Jordan. Before that my fuel meter has always worked pretty well on these past two years. It can't be the heat because we had similar temperatures last summer in Finland and no problems with the meter then.

So I guess there's nothing I can do about it then. Better start getting used to resetting the trip meter after fill ups.

Jami

I ignore the gauge completely and use the trip meter to know when to fill up..

I suspect the fuel guage is on the left hand side of the tank so when the bike is resting the fuel level seems higher on the meter. When you turn it on again afterwards the level seems to have 'recovered' until the meter realises the level is lower when the bike is upright.

Also noticed my level drops from full quicker than it used to, but as other say full and f-trip are still correct and that's all I ever used it for anyway (and I always reset the trip each fillup anyway)

slightly off topic
 

lol too many traffic light GPs plus I did often find that WOT was a good place to be when making progress :). Rrobably why I felt the need for the bigger brother.

Once you last bar starts flashing you have about 7 litres of fuel left, which is just less than a third of you tank. If you reset your trip when you filled up you have about half that distance available to you (eg if you have done 160 miles you can do a bit under 80 in reserve). To add a bit of safty margin I'd take 10 miles off that, and another 10 if you brim the tank when you fill it, ie 60 miles in reserve in this example.

In practice I could always guarantee getting 200 miles from a tank (even when getting only 40mpg due to stop/start and short runs). My lest efficient tankfull (39.88mpg) gives me a range of 202 miles to a non-brimmed tank.

The closest I got to running out was after 192 miles (about 40-50 on reserve) I only got 21l in the tank (not brimmed) which means I had about 2l (or nearly 20 miles) left.

Yes. Down to one bar, then the bar will start flashing and the F-trip will start counting up from zero.

I reckon you'd struggle to burn through the reserve capacity in less than 40 miles in normal use. Tripletom did try it with a fuel can on the back, and got 50 miles to dry, and I'm sure he won't mind me saying that he's not one to nurse it along to conserve fuel.

I hardly ever fill up before it starts flashing, and if I'm just commuting I'll usually run 20 miles or so into reserve before I even think about going for fuel - but then I know where the petrol stations are, and doing about 200 miles a week I spend enough time stood in them as it is without filling up more often than I have to :D

Are your brakes siezed on? :D

Lol. Unfortunatly it's just the local riding conditions, I still get 60mpg or so when in the UK on decent lenghth journeys.
When I use my bike in Guernsey I'm usually commuting, so that's less than 3 miles per trip, from cold each time with the journey being fairly stop start (though less than in a car). Like many I like to abuse the throttle as often as I can (while keeping within the 35mph limit) so that does not help either. I think you'd be hard pushed to get much worse conditions for fuel consumption (but at least those 150 miles will last me a month or so!)

I would be happy if the f-trip was correct but that is not the case anymore.

Jami

Likewise mine, it seems to trigger early now, but again if I park it overnight it can 'recover' enough to reset it back to the normal trip counter (takes five miles I think) then 5-10 miles later it will trigger again.

Wierdness.

but wouldn't frothing result in teh opposite effect: having higher readings during / right after a ride and lower after standing the bike for a while?

Mine does it as well btw. Just like my TDM used to do. I just ignore it now. Just start looking for petrol after the F-trip shows 10-20km. Most of the time I ride with people that need to fill up more often anyway. Then I don't even get to the F-trip.

Could be the windchill when riding causing the fuel to contract that gives a lower reading. Then when you park up the lack of windchill and heat from warm engine causes the fuel to expand hence giving a higher reading.

BTW, I regularly run 40-50 miles in to reserve. Most was about 70 odd miles (Towcester to Guildford).

I Travel 120 miles a day. I fill up every other day at about 235 miles. That used to be 30 mile sinto the f-trip in the summer but is now about 40-50 miles now the weather has cooled down?

I get about 21-22 liters in but i do fully brim it so there is probably about 2 liters left.

It always makes it to the fuel station so i have given up careing now.

I haven't really go empty on mine yet, but last time I checked I was able to do 90Km (56 miles) and still had some fuel left. By my guess, I could have easily reached the 150Km mark.

I've also found the fuel meter to be quite erratic. I just wait until the F-Trip comes on the first time (yes, because if you stop for a while it won't be in reserve anymore...) and then count the Km from there.