Fuel Dip Stick?

Discussion in 'The Garage' started by GoGoGavin41, Jun 19, 2017 at 7:10 AM.

  1. GoGoGavin41

    GoGoGavin41 Qapla'

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    Looking for ideas here...

    I have rather large tanks on a bike I'm currently racing in stage rallies (Safari tanks on a 990 Adv). There are many instances where I'd like to be able to pretty accurately determine how much fuel I've used between services so as to add exactly as much fuel as I feel I need to make it to the next service. On stock tanks I usually just fill them up (two 2.5 gal tanks), but with two ~5.5 gal tanks that's a lot of fuel to carry unnecessarily.

    I envision something like a long, plastic dipstick that I set into a notch with known fuel heights on it - I could easily determine this by just draining the tank, pouring a gallon, measuring and marking, etc. It seems like the red path would be best to determine fill height, a shape which probably lends itself to a clothes hanger, but I'm worried I'd bend it out of shape accidently.

    [​IMG]

    It's fairly hard to determine consumption due to differences in terrain, transit length, how well the bike is running, etc. I would loved to have gotten the translucent tanks but these opaque white ones were on the bike when I bought it...

    Any ideas?
    #1
  2. Flipflop

    Flipflop Been here awhile

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    Look at fiberglass sail battens. They flex, and are tapered on one side so you have something half way thick to hold onto.
    #2
  3. 16VGTIDave

    16VGTIDave Reaver made me do it...

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    What about making a "sight tube" so you can see the fuel level? Then you could fill the tank with measured quantities and mark the levels accordingly.
    #3
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  4. GoGoGavin41

    GoGoGavin41 Qapla'

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    Hmm, this looks like it'd be ideal assuming gas (or ethanol) doesn't dissolve fiberglass. Not sure about that, the interwebs seem to say it depends on the resin.

    Also interesting. Any opinion on where to put it? Seems like it'd be pretty vulnerable on a bike that gets dropped a lot.
    #4
  5. troidus

    troidus Long timer

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    Could you french the tube into the side of the fairing, so it's protected? (Wouldn't really be frenching, it'd be just leaving a cutout so you could see the tube behind the panel.)
    #5
  6. usgser

    usgser Long timer

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    Why not just a couple fittings and a length of clear tygon fuel hose connecting them as a a sight glass/tube?
    #6
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  7. 16VGTIDave

    16VGTIDave Reaver made me do it...

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    Hard to answer that without being able to see the tank in person. The optimum would be close to the lowest point and the very highest point of the tank. Obviously being kept away from moving parts, hot parts, or vulnerable areas like the leading edge or outside surface. Looking at your pic, the opening in the side of the tank looks like it might be a good location for a indicating a significant portion of the tank volume. It looks like you could install fittings at the top and bottom of that opening and connect them with a translucent tubing. Tygon like @usgser suggested would be a good choice.

    Keeping a pre-cut length of tubing with clamps installed in your tool kit, or jacket pocket, would ensure you'd never need to repair a damaged tube!
    #7
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  8. GoGoGavin41

    GoGoGavin41 Qapla'

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    So you guys are talking about something like this right?

    [​IMG]

    You're probably right about the recess being the best place for it. Nowhere feasible to put it inside the frame and anywhere else outside the bike would be vulnerable to damage.

    It does make me pretty nervous putting more holes in my tank than there already are - especially a race bike. Something passive like a stick seems much lower risk to me.
    #8
  9. Schmokel

    Schmokel Riding gear saved my life.

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    Use the odometer. Keep things exciting. :D
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  10. pigjockey

    pigjockey Hognuts the T-bagger

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    A piece of braided fishing line and a bass casting sinker on the end.
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  11. Flipflop

    Flipflop Been here awhile

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    It doesn't dissolve it if you don't store it in the tank. I just wipe it down and put it away. Takes some study to find a marker that will live through gasoline though!
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  12. Flipflop

    Flipflop Been here awhile

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    Also you can take a clear piece of vinyl tube and poke it down in the tank, hold your thumb over the end to keep it running out and pull it up quickly and get a read on your depth... But you've got to have a half way clear run to use that.
    #12
  13. VX Rider

    VX Rider Long timer

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    Just use your trip meter

    I have no fuel gauge, I use analog trip/odometer to judge fuel remaining


    Unless you removed stock instruments you have two trip meters and a fuel trip meter
    #13
  14. MATTY

    MATTY BORDER RAIDER

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    By my north country reckoning... Far from infallible i admit..I just open the gas tank cap and look in:lol3 ...I use my eyes:lol2, if i ever decide i want to know exactly whats in when say the central tank profile is exposed when in line with the filler neck just drain and measure whats in at that point . Then you will know at that point the tank has lets say 7 litres left in it etc etc .
    #14
  15. trc.rhubarb

    trc.rhubarb ZoomSplat!

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    What if you went real low tech? Assuming they are plastic, they shouldn't be completely opaque... just mostly.
    You could still mark the tank with black markers, tape, whatever at each 1 gallon level then open the cap and see a dark stripe indicating the fuel height to the nearest marker.
    You might even be able to do the same but rig a bright LED under the tank and turn it on via a momentary button so that you can light up the fuel level to be seen from the outside against your markings.

    Or, you could mark a length of line, wire, string, and attach a float to it.
    Drop the float in the tank and note the depth it drops to.
    #15
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  16. Salsa

    Salsa Been here awhile

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    For a sight gauge,

    Tee in the fuel line after the shutoff and run the line above the tank, loop it and point it down. Put a filter on the end.

    Done.

    Don
    #16
  17. ohgood

    ohgood Just givver tha berries !!!

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    get a long zip tie and notch it at each gallon.
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  18. Spyrious

    Spyrious Want to go offroad

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    This!

    Sent from my HTC One M9 using Tapatalk
    #18
  19. baka1969

    baka1969 Veteran Bubblehead

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    This is an easy and effective solution. One I was going to suggest with the exception that I'd clip off the top end (with a binder clip) instead of using my thumb. You could mark off the tubing in 1/2 gal increments.
    #19
  20. GoGoGavin41

    GoGoGavin41 Qapla'

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    If I can find some semi-rigid clear tubing this is probably the ticket. I know from experience that regular floppy vinyl is pretty difficult to get to the bottom of these tanks for siphoning, nonetheless trying to get a straight, consistent run for measuring purposes. Maybe even zip tying regular vinyl to a coat hanger or one of these other semi-rigid options.
    #20