Is the VFR800 Gas Gauge Accurate?

[michael]

Recently I have gotten allot of mail from people complaining that their gas gauge is not accurate. I decided to do my own little test, by refilling each time I got to a new level on the gauge and noting how much gas was necessary to fill it up.

When all but one bar is lit on my fuel gauge I am 1 gallon from full or at 4.5 gal

When all but 2 bars are lit on the gauge I am 2 gallons from full or 3.5 gallons

When all but 3 bars are lit on the gauge I am 3 gallons from full of 2.5 gallons.

When gauge shows half tank (half the bars are lit) I have only 2 gallons of gas.

When only 3 bars are lit I have about 1.5 gallons

When gauge shows 2 bars lit I have about 1 gallon.

When gauge shows 1 bar flashing I have only about .5 gallons left.

Summary
-0 bar 5.5 gal (Indicated Full)
-1 bar 4.5 gal
-2 bar 3.5 gal
-3 bar 2.5 gal
-4 bar 2 gal (Indicated 1/2 tank)
-5 bar 1.5 gal
-6 bar 1 gal
-7 bar .5 gal (Flashing 1 bar)

My Theory is that the float level gauge does not take into account that top few inches of gas depth in the tank hold much more fuel that the bottom few inches of gas depth because the frame is in the middle.

[grinder]

One thing I have noticed with the gas gauge is that it is sensitive to both lean and whether you are climbing or descending. Overall I find it pretty reasonable considering how hard it is to deal with the highly variable shape of a motorcycle gas tank.

[reg71]

Originally Posted by grinder

One thing I have noticed with the gas gauge is that it is sensitive to both lean and whether you are climbing or descending. Overall I find it pretty reasonable considering how hard it is to deal with the highly variable shape of a motorcycle gas tank.

true. I was noticing that on my ride back form northern cali yesterday.

[Saint_Craig]

I find it to be fairly accurate though when the red bar starts to flash on my 02 I have exactly 1 gallon of gas left in the tank.

[grinder]

Yes 1 gallon is about the same for me on my 2005 although I once almost got caught as I was riding a very twisty road (fun!!!) and it came on with about half a gallon to go. A bit of a surprise to say the least. I guess that it was the sloshing of the fuel that tricked the gauge.

Enjoy.

[brianereed]

I haven't found as much of a variation from the owners' manual as you. When my "reserve indicator" flashes, I have about one gallon left.

I like your test though, I think I might do the same.

[Hurryin' Hoosier]

My VFR has a low fuel fail safe.
It automatically kills the engine when the tank is empty. It cost me a case of beer this fall, and a $10 plus gas the year before.
Now I don't let the blinking bar stay on as long.

It is nice to see the homework you did. It helps figure out that first direction to go on those 'gotta ride' early mornings (i.e. toward town, away from town).

[Saint_Craig]

Originally Posted by Hurryin' Hoosier

My VFR has a low fuel fail safe.
It automatically kills the engine when the tank is empty. It cost me a case of beer this fall, and a $10 plus gas the year before.
Now I don't let the blinking bar stay on as long.

It is nice to see the homework you did. It helps figure out that first direction to go on those 'gotta ride' early mornings (i.e. toward town, away from town).

If I am doing a bit more of the sport riding than the tour riding, the blinken light comes on earlier, than it would if I was more vertical all the time. But in "tour mode" I have 1 gallon when the light comes on, which is about 40 mi. (Riding style immediately changes from spirited to granny like.) I'f I'm riding in more of the sport mode, It seems to come on at about 1.2 gallons, and will go out again if I revert to tour mode and the liquid settles down int he tank.

[OhioVFRMan]

Don't know how much mine holds when the blinking starts, but when it happens & I fill it, I never can put more than 4 gallons in it. Maybe need to put it on center stand since angle it rests at seems to be a big factor when filling up.

[ranree]

I have found similar results as well. The gauge is very accurate under fairly upright conditions.

[hustond]

Sorry, but I have to ask.......24 hours on the Black Bird?

[Swoop]

Has anyone ever managed to get the top bar to light up? No matter how full I get the tank, the LCD indicator refuses to become part of the information process...

[NorcalBoy]

Originally Posted by Swoop

Has anyone ever managed to get the top bar to light up? No matter how full I get the tank, the LCD indicator refuses to become part of the information process...

I have only done it once, as a test, but mine lights the top bar, but only if I fill it ALL the way to the top. This is hard to do because it has a tendency to make a mess. Living in CA it's a pain because you have to hold the friggin' vapor recovery condom back while filling. I know, I know, Aerostich makes a key type device to do this for you but I don't want some gas scented thing stinkin' up my tank bag, pocket, etc.

There aren't many places you can go to run out of fuel, other than being unattentive or lack planning ability, so I don't worry about it much. Having just a little bit of desert racing experience, I have learned a few tricks. Liquid camp fuel bottles are a good backup in case your unsure of your distances on long or remote trips.

Overall, I think the gauge works pretty well and the accuracy is acceptable.

[Mac]

I fill mine to the top, minus ( ) that much. Top bar lights up for about 20 miles.
No problems with overflow.
Too chicken to go more than 190 highway miles with out a refill. I have never seen the red bar.
Closer to home, I fill up about every half tank.

Mac

[Saint_Craig]

Originally Posted by hustond

Sorry, but I have to ask.......24 hours on the Black Bird?

Drunk driver + Ford LTD + Me + red light = Ionized.

I should image the copy of the police report, all emergency personnel involved said I was lucky to be able to crawl away. since the SOB, had a BAC of 1.5 was driving without insurance or a license.

Needless to say the only salvagable component of the blackbird was the Triple Trees.

Swing arm bent, tank crushed, sub frame orgami'd engine cracked....

the cop who witnessed the event, when visiting me in the hospital said said he clocked the driver at over 100 in a 35.

this is simply why I will never win the lottery, already used all of my luck.