I ran out of petrol.

[alans1100]

Car is not that accurate either. This might shed some light on speedo laws http://www.mrasa.asn.au/speedometers.shtml

[Kev Murphy]

My GPS indicates that my speedo has a 10 KPH error, but I travel at GPS speed. The 620 k distance recorded by the speedo then becomes a true distance of 558 km per tankfull.
I have an upcoming trip in two weeks from Portland, Vic to Morgan, SA, which by google maps is a distance of 632 Km, so it will be interesting to check the actual speedo reading for this trip.
I have never actually done a fuel reading by true distance covered, but I know from previous trips to Morgan that I require an extra 4 litres more than the tank holds to get there. This drops my true economy to 19.75 Km/litre from 22 km/litre as indicated by the odometer.
It also explains why I can ride from here to Adelaide on one tankfull, and still have a splash onboard when I arrive, because the true distance is 533 km, not the odometer reading of 587 km. Still, 19.75 km per litre is pretty good economy for highway speeds.

Hmmm... this also means my bike is younger than I thought, only 150 k on the clock,not the 170 k recorded?
Sheesh!, no wonder the timing belt showed no sign of wear when I changed it, at an indicated 150k?




Edited to correct typos 

[Brock]

Cars over read as well.

[Gatey]

Great answer Kev and you make an excelent point about the true age / milage of our bikes too.
And an ST or similar that's producing 19.75 km/l is working well.


Even if your ( the general mobs ) bikes is READING 19.75 km/l that's probably not a bad figure across the board.

[Brock]

The speedo is out, but the Odometer is accurate

[Kev Murphy]

The speedo is out, but the Odometer is accurate

    so... they fit an instrument that is correct in one aspect, and confusing in another. One would expect that if one travels at a constant  indicated 100 kph, then 60 minutes later one would be 100 km further on ones journey, not shortchanged by a factor of up to 10%.  Where did Honda get this idea from, have they been adapting instruments to this idea from Australian Politics where we are told one thing, and presented with another??
Its known worldwide as 'The Porky Pie Principle', (altho it should be spelled 'Principal', because it invariably causes us to dip our hand into our pockets yet again)

[Brock]

Its not just Honda, its every one cars included. Its all to do with the tolerance of the instrument, and the rules (ADRs for example) that state how the instrument must indicate.

The speedo can be made to be accurate on speed and distance ( see police spec bikes), however, changing tyres can change the reading. also tyre pressures can affect the speed indication.

One of the design rules for a speedo is that it must not under read IE, indicate 95 when true speed is 100. The fix is to make the speedo read 100 when doing actual 95. This way, the manufacturer cant be held responsible for you exceeding the speed limit. Digital computer driven speedos are even easier to make over read. The computer will do something like  "Speed indicated = true speed +1% true speed +2"

[Gatey]

The speedo is out, but the Odometer is accurate

No Brock both measures are out hence the corrected distances IBA will endeavour to check.
Between a well kept FJR that I know and travel with compared to my TDM and my ST over thousands of K's together....and similar with HD's, Trumpys and so on the odometers never ever tally with each other ( on that very same trip together)  or the actual distance as measured on bike mounted GPS and the various map systems.

Its disappointing realy.

Kev rest assured its not a Honda thing...its in every bike on this planet regardless of colour or creed.

[Kev Murphy]

It will be interesting to check readings on my upcoming trip in a weeks time, compared to google, just to satisfy my own curiosity. 

[Gatey]

Just have a real good look at your google route Kev. Roll down to check its not taking you around town to get at the GPO. Mildura is one trap that comes to mind. BUT Those little towns never seem to add that un-expected loop. All Google maps route off the nearest GPO. Examples of that twisted sister are places like Tamworth which has several GPO areas within its boundary,Dubbo another & Mildura as noted, Correct Me if I'm wrong, Mt Gambier too has an east and west GPO. I know it used to.
Port Augusta will post a distance and only once you read through the rout directions will you discover that entry from the Adelaide side for an exit to the north will more often than not want you doing a loope round Bond St, Alexander St and Coonara ( past the LPO to bring you back at the lights you passed through a few moments ago from the right.

Point here is take a bloody good look at your route and adjust accordingly so as not to map extra distance and stuff up your test Kev. Results are often what others are looking for.

[Kev Murphy]

I don't necessarily follow the GPS directions into towns, but usually just pass straight through them. 

[Gatey]

Correct we all do but Google map will sort your route to GPO.
You end up with a Google map route figure then the GPS on your bike then the dash Odo and after that its sort of X-Files to probe the results.
Keep us posted Kev. If you get the opportunity test the corrections over each K in a 5Klm run against the distance markers. Just for the fun of it.

[Kev Murphy]

Will do.

[alans1100]

I planned my route for last years Border Ride and Google gave me a 2179 return and odo gave me 2135 km return and GPS gives 2042 return so I think my odo is more accurate than Google compared to my GPS

[Biggles]

When I'm using Google maps that way, I put in the town's main enroute intersection co-ordinates instead of the town name.  That defeats the nonsense Gatey warns about. 
Another thing it does that annoys me is add in loops when you drag the route to a different road.  You can sometimes defeat that by zooming in close to be precise about where you're dragging the dot to.

[Kev Murphy]

The map above is direct, point to point, door to door.. no diversions. Be interesting to check my odometer reading when I get there next Friday

[marty]

never trusted fuel gauge or lights, fill up , reset trip. when its gets to 400 fill up    simple simple

[Kev Murphy]

Why should I fill at 400, when I regularly travel well over 500 per tankfull?

[marty]

well Ive had mine along time its a 1990 model  27 litre tank 16k per litre = 432  400 gives me 32 k lee way  but thats just me and the way I ride. you get 500 still easy :)

[Kev Murphy]

Mine is a 98 model, non ABS, and I have ridden it over 80,000 km in the past 4 and a half years, so I am pretty aware of how little fuel it guzzles on trips. Nothing wrong with 16 k per litre, but I consistently get more than that, even when tootling around town.

[Brock]

Its actually a 28 liter tank, a couple of times its taken 27.6 ltrs

Once I ran out.....

[alans1100]

well Ive had mine along time its a 1990 model  27 litre tank 16k per litre = 432  400 gives me 32 k lee way  but thats just me and the way I ride. you get 500 still easy :)

Before my fuel reserve light failed I would generally get around 400 km when the light lit up. Refill was generally 24 litres plus/minus 1/2 a litre so I guess average was about 16.7 k/l which is fairly close to my current average in the signature below. I aim to fill up now between 350-400km or about 300-350 km when towing.

Its actually a 28 liter tank, a couple of times its taken 27.6 ltrs

Once I ran out.....

I actually managed a fill of 27.5 litres; once ever for 472 km