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You know how our fuel gauge does the giant dive from the high board and shows only 2 out of 5 bars at approx 80 miles, one bar at around 105 and flashing reserve at about 130..when there is still plenty of fuel left in the tank. I've personally gone as far as 180 miles on a tank. On my recent trip to North Carolina, I usually filled up at approx 140 miles and not once had to put 3 gallons in it.
The other day I filled up my Honda Civic. It's got 20 of those little fuel bars. I drove 50 miles and it is still showing 20 fuel bars. In theory at 50 miles per bar ( if these gauges were linear which we know they are not) then I should be able to drive 1000 miles on a tank of gas. Alas, I cannot. It will go about 400 miles before needing gas again. At some point it too will drop bars faster than usage would indicate.
So which is better, one that drops fuel bars too fast early on like our bikes? Or one that waits and then drops them all of a sudden like my car? I think the better question is, why can't they make one that is somewhat accurate.
Hands up? Who still panics, when they are out riding and get down to one bar?
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I'd rather have something like my Honda ST1300 that shows miles to empty rather than fuel bars. I have no idea how far I can go on a tank of gas on my CB1100 because I fill up when the bar starts flashing.
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I'm of the mind that reading too low is better than too high, wouldn't want to end up pushing this big baby. And yes, I'm a one-bar panic. Really though, I'm just going by the trip odometer and not paying as much attention to the fuel gauge. Probably due to all the old bikes I've owned not even having one!
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(07-28-2013, 01:38 AM)Firstfour_imp Wrote: I'm of the mind that reading too low is better than too high, wouldn't want to end up pushing this big baby. And yes, I'm a one-bar panic. Really though, I'm just going by the trip odometer and not paying as much attention to the fuel gauge. Probably due to all the old bikes I've owned not even having one!
+1 on preferring too low over too high...
From what I understand designing a fuel level gauge must be hard. The fuel is sloshing around all the time fore and aft, left and right. The only thing you can hope to get is some kind of an average of all the fluctuating readings (either have a sender that tells what the level is at some place in the tank accurately and average the readings over time, or have some kind of damped reader that doesn't respond quickly to fluctuating level changes and get some kind of average from the reader itself).
Either way it seems hard to do, full of tradeoffs.
I wonder how aircraft do it.. I hear that they measure fuel by mass.. now that seems like it might be easier to get a read on (when the plane is flying straight and level at constant velocity, which is probably most of the time (?)).
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(07-28-2013, 01:38 AM)Firstfour_imp Wrote: I'm of the mind that reading too low is better than too high, wouldn't want to end up pushing this big baby. And yes, I'm a one-bar panic. Really though, I'm just going by the trip odometer and not paying as much attention to the fuel gauge. Probably due to all the old bikes I've owned not even having one!
I hear ya, hard not to watch or look at the dang gauge though lol
Heres an old guys thing for you..on my early bikes we'd often unscrew the gas cap, rock the bike back and forth between our knees and listen to the volume of the slosh to see how much gas we had. If we did run out, we'd switch it to reserve. When that would run out, we'd often lay the bike down on the left hand side and slosh the gas that was stuck on the right side of the tunnel over to the left hand side, being as how the reserve petcock was on the left and in the early days they didn't link the two sides. Laying it over would get enough gas to the petcock for another few miles.
I actually don't miss those days lol
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Thanks for the description.. well, we're spoiled with our motorcycle and car fuel gauges then. I'll take the convenience in return for a little inaccuracy.
I'll also never take commercial air travel so lightly again after hearing this !
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(07-28-2013, 01:38 AM)Firstfour_imp Wrote: I'm of the mind that reading too low is better than too high, wouldn't want to end up pushing this big baby. And yes, I'm a one-bar panic. Really though, I'm just going by the trip odometer and not paying as much attention to the fuel gauge. Probably due to all the old bikes I've owned not even having one!
I'm with firstfour, I rely on miles traveled after the last fill up, in my case partially out of habit and partially in reaction to the fact that the current gauge is so pessimistic and non linear (dropping a bar very soon after fill up) that it is almost useless. Note that a 'miles remaining' indicator would also be similarly pessimistic unless they fixed the calibration of the fuel level sensor in the first place.
The fuel gauge is so useless that I'd gladly trade the fuel gauge for a gear position indicator, which would be more useful in my opinion.
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If the gauge flashes at about 130 miles every time, which is what at least a couple of us seem to be saying, then it's accurate enough for me. I know I have 40-50 miles left at that point which is plenty of time to find a station and, if I need more time, I just start looking at two bars. Seems to me like this is just not a big deal.
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(07-28-2013, 01:28 AM)The ferret_imp Wrote: You know how our fuel gauge does the giant dive from the high board and shows only 2 out of 5 bars at approx 80 miles, one bar at around 105 and flashing reserve at about 130..when there is still plenty of fuel left in the tank. I've personally gone as far as 180 miles on a tank. On my recent trip to North Carolina, I usually filled up at approx 140 miles and not once had to put 3 gallons in it.
The other day I filled up my Honda Civic. It's got 20 of those little fuel bars. I drove 50 miles and it is still showing 20 fuel bars. In theory at 50 miles per bar ( if these gauges were linear which we know they are not) then I should be able to drive 1000 miles on a tank of gas. Alas, I cannot. It will go about 400 miles before needing gas again. At some point it too will drop bars faster than usage would indicate.
So which is better, one that drops fuel bars too fast early on like our bikes? Or one that waits and then drops them all of a sudden like my car? I think the better question is, why can't they make one that is somewhat accurate.
Hands up? Who still panics, when they are out riding and get down to one bar?
hands up
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Tried to put in 3 gallons today after riding with a flashing indicator for around 7-8 miles..stopped at 2.9 dint want to put that last 1/10th as I wanted to keep the filler neck clear.. It would definitely have filled the neck and overflowed..
So a safe bet would be like 2.5 gallons once the flashing begins..
