Fuel Guage 2018 Speedmaster, Bobber, T120

Discussion in 'Bonneville' started by Beerman, Sep 17, 2018.

  1. Beerman

    Beerman Guest

    #1 Beerman, Sep 17, 2018
    I'm finding it difficult to read the electronic fuel guage on the Speedmaster 2018. It's a 'miles left in tank' range reading, and even when full it rarely shows much above 120 miles (when I think there is 160 miles + in the tank). The mpg reader says that I am averaging 64mpg. The 12 litre tank, when you do the arithmetic (and assuming we're talking UK imperial gallons) at 64 mpg yields 168 miles in the tank - the reader is quite a long way off that.

    What it means is that when the 'guage' says I have 20 miles range left, I really don't know how accurate that is.

    I'd be interested to know if this is a widely held view on the accuracy of the guage - or not. I guess it's the same on the T120 and Bobber, at least.

    Beerman
     
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  2. dilligaf

    dilligaf Guest

    #2 dilligaf, Sep 17, 2018
    Same here mate :confused: but I don’t think I’ve ever had a bike with what I would call an accurate fuel gauge :confused:
    I do like the guage on NUDGER because it gives a good idea of range left :)
    I particularly like the way it recalculates the range left depending on how hard your working the engine eg hard accelerating and uphill and the range drops off :( easy cruising and downhill and the range increases :grinning:
    A good example of this is when I’m using my trailer full of camping gear and alcohol :yum
    After leaving the Spat out of Hull rally on Sunday I decided to fill up before heading home :) as I was waiting for traffic to clear so I could exit the garage I checked the range and it said 128miles:) as I accelerated through the gears to fourth I checked again and it had dropped to 93mile range :(
    Riding through Yorkshire countryside it fell as low as 72mile range :confused: this was using mainly third and fourth gear :)
    After joining the A19 dual carriageway and cruising at about 80mph mostly sixth gear it settled for quite some distance at mid 80s range :)
    When I got home it said I had 42miles left to go :)
    Helmsley where I filled up is about 65miles from where I live :) giving me and NUDGER a range of over 105miles pulling a trailer and riding quite hard :eek:
    I Reckon NUDGER is good for over 150miles per tank without the trailer but when the warning light comes on I’m looking for a garage regardless of what the range says :p
     
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  3. Dartplayer

    Dartplayer Crème de la Crème

    Aug 8, 2018
    7,608
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    New Zealand
    #3 Dartplayer, Sep 19, 2018
    Last edited: Nov 26, 2018
    Experience with my 2018 Speedmaster is that light has 3l left on 12l tank, so 1/4 left. Even with metric measures that should give 60km/35miles.
    I’ve been doing 210km with a bar left which would point to 240km/150miles. I think there may even be more based on quantity to fill on the stand not being 9l when light first comes on. Hope this helps
     
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  4. David Simpson

    David Simpson Member

    Feb 13, 2018
    77
    18
    Boston UK
    #4 David Simpson, Sep 21, 2018
    on my 2018 T120, the fuel gauge at full reads 190-200 miles, fuel light at about 140-150.
     
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  5. Wessa

    Wessa Cruising

    Apr 27, 2016
    11,725
    1,000
    North West England
    #5 Wessa, Sep 21, 2018
    Yep my speedmaster is about the same. Average mpg is at 66mpg on the computer (which I have not reset since new) and when I fill up it shows cicra 120 miles range. Reserve light normal comes on at around 100 to 110 with anything from 30 to 35 miles range left, so I reakon that if I ran the tank dry it would return circa 150 to 160 mpg.

    To be honest I don't think the guage is designed to be that acurate, only there to provide a guide on fuel levels and range to run out. Running around locally I don't monitor or worry about how much fuel I have on the bike. If I do travel further afield I usually plan my refueling based on 100 mile stops.
    Wessa
     
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  6. Dartplayer

    Dartplayer Crème de la Crème

    Aug 8, 2018
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    New Zealand
    #6 Dartplayer, Sep 21, 2018
    Fuel Capacity on T120 is slightly higher at 14.4 L / 3.8 US gal / 3.2 Imp gal
     
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  7. Burglar

    Burglar New Member

    Nov 26, 2018
    1
    1
    Maryland
    #7 Burglar, Nov 26, 2018
    How you getting 64mpg when I'm @ consistantly at 46mpg. I go fast but not that much.
    Speakes to accuracy not to be trusted. Keep her topped off is all I can do.
     
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  8. Dartplayer

    Dartplayer Crème de la Crème

    Aug 8, 2018
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    #8 Dartplayer, Nov 26, 2018
    Hi Burglar, Fuelly website has you about right for newer 1200, at 48.2 mpg

    B2C1A704-CAAA-4CC1-A03F-28FF24B098B8.png
     
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  9. Burglar

    Burglar New Member

    Nov 26, 2018
    1
    1
    Maryland
    #9 Burglar, Nov 27, 2018
    Regardless of actual mpg issue is accuracy of miles left to fill. To this I have only got down to 30 miles left.
    Probably need to run her dry to find out. If I do that I'll let you guys know.
     
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  10. Drummer

    Drummer Member

    Mar 4, 2016
    13
    8
    Leeds
    #10 Drummer, Mar 4, 2019
    Sorry to be late contributing to this thread, but you must compare apples with apples. 64mpg quoted is per UK gallon which is 20% more than a US gallon. Your 46mpg to the US gallon equates to around 55+mpg in UK terms. Hope you feel happier.
     
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  11. BigCLM

    BigCLM Senior Member

    Nov 30, 2017
    1,018
    243
    San Rafael, CA
    #11 BigCLM, Mar 4, 2019
    I have a Street Twin and don't rely on the computer gage. (similar experience). I know my bike gets 65+ MPG as I normally ride so can go maybe 200 miles to 'empty'. To be safe I fill up at <150 miles. I fill up probably more often that I need to - but I have never run out of gas !!
     
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