True MPG?

[ron]

Having nothing to compare,I am looking for opinions as to the accuracy of the trip computer regarding MPG.I always fill to 1st click of pump & round to next £.I divide miles by litres filled x 4.54 to give MPG.The computer is always optimistic by as much as 8-10%.I have also found the slope of the forecourt makes a difference,filling with the filler neck uphill,I can get 4+ extra litres in.I want loads of controversy please.

[nil by mouth]

I can't find my trip computer cratch: when I do I'll gladly help you out the best I can

[geoff]

Ron you need to see the fuel at the top of the filler pipe rather than use clicks - the " eyes have it "
I agree with the forecourt and always try to use the same pump due to camber variations.

[Coco]

Ron you need to see the fuel at the top of the filler pipe rather than use clicks - the " eyes have it "

NOOOOOOO. Us motorcyclists will not thank you for that

[evdama]

MPG Calculator and the trip combobulator give near identical results for me..

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Ron you need to see the fuel at the top of the filler pipe rather than use clicks - the " eyes have it "

NOOOOOOO. Us motorcyclists will not thank you for that

Back in the day I wiped a brand new 4 into 1 exhaust off my XJ550 due to the roundabout being lubricated with deisel by the lorry in front.

[ron]

Ron you need to see the fuel at the top of the filler pipe rather than use clicks - the " eyes have it "
I agree with the forecourt and always try to use the same pump due to camber variations.

Thanks Geoff,but as Coco said,diesel is deadly for bikes(can't spell motorcycle).That's why I use my system which I think averages out OK.
I went to Germany as per my other thread,The computer said 80+ mpg But my Einsteinian reckoned it at 72,hence my question.

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MPG Calculator and the trip combobulator give near identical results for me..

---

Ron you need to see the fuel at the top of the filler pipe rather than use clicks - the " eyes have it "

NOOOOOOO. Us motorcyclists will not thank you for that

Back in the day I wiped a brand new 4 into 1 exhaust off my XJ550 due to the roundabout being lubricated with deisel by the lorry in front.

I notice you have an enterprise,surely that runs on Dilithium crystals?:lol:

[evdama]

Ron you need to see the fuel at the top of the filler pipe rather than use clicks - the " eyes have it "
I agree with the forecourt and always try to use the same pump due to camber variations.

Thanks Geoff,but as Coco said,diesel is deadly for bikes(can't spell motorcycle).That's why I use my system which I think averages out OK.
I went to Germany as per my other thread,The computer said 80+ mpg But my Einsteinian reckoned it at 72,hence my question.

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MPG Calculator and the trip combobulator give near identical results for me..

---

Ron you need to see the fuel at the top of the filler pipe rather than use clicks - the " eyes have it "

NOOOOOOO. Us motorcyclists will not thank you for that

Back in the day I wiped a brand new 4 into 1 exhaust off my XJ550 due to the roundabout being lubricated with deisel by the lorry in front.

I notice you have an enterprise,surely that runs on Dilithium crystals?:lol:

Unfortunatly yes it does - a chap at work siad he would sell me some crystal but I was quickly ushered away from him.

[Noel Brig]

Having nothing to compare,I am looking for opinions as to the accuracy of the trip computer regarding MPG.I always fill to 1st click of pump & round to next £.I divide miles by litres filled x 4.54 to give MPG.The computer is always optimistic by as much as 8-10%.I have also found the slope of the forecourt makes a difference,filling with the filler neck uphill,I can get 4+ extra litres in.I want loads of controversy please.

Yes you do need to fill up at the same pump in the same forecourt to make sure you are filling to the exact same level - you do get quite a bit more in if the vehicle is tilting forward to tilting backwards, hence can be quite inaccurate, however if you take an average over 3 or 4 fills inaccuracies become less significant.

I found the fuel warning light coming on is also a reasonably accurate way of calculating distances between fill ups - it also means you do not need to fill it to the top. (both berlingos I have owned have had very accurate fuel gauges)

The other thing you need to do is establish the accuracy of your mileometer; My MKII over estimates distances by 1.75% (40lb/sq"" with 6mm tread) and my MKI over estimated by 4.4% with similar tyre set up. Don't use a GPS to compare distances covered; they cut corners and will understate - they are good to use to check speed while cruising at steady speeds on motorways etc, but not distances on country roads.
To check distance, compare some reasonable length journeys against the likes of.
http://www.bikehike.co.uk/mapview.php
I have not been able to fault it's accuracy within the UK, have been told it is not so accurate in france and germany!!!!

[ron]

Hi Noel,Thanks for your input,but I can't see how not brimming will give accurate results.Surely that is entering the realm of guesswork.I do use route planning to check distance..Also,in 30,000m I have only seen the low fuel light once & drove for 50 m,finding I had approx 3-4 ltrs left when refilling.As you say,it must boil down to mileometer error,but my regular long trips to family etc show my mileage lower than Google etc,but consistent with family etc coming here in their own vehicles.The plot thickens.

[hachiroku]

If I want to record mpg then when I fill up I make a note of the litres put into the tank, the price per litre, and the mileage on the odometer. I then put the info into fuelly.com and keep a track of things.
Not started doing this on the Berlingo yet, but will make a start next week.