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Instrument accuracy (or lack of)

8832 Views 22 Replies 9 Participants Last post by  Roymans
Was planning a trip away on the 790 when I thought that with the 14 litre tank maybe I should check how accurate the instrument readings are, so with the aid of a GPS and refuelling at several different fuel stations in case the pumps were inaccurate I came up with some surprising findings.

A + reading means the instruments read higher than the true distance.

Speedometer ......... + 5%
Trip meter ............. + 2.5%
Fuel Range ........... + 5%
Fuel Consumption + 18% ***

Well the speedo error was as expected, +5% error is almost an industry standard these days, my last few cars had a +5% error and also my last 3 or 4 bikes

The trip error of + 2.5% is a little high compared to Jap bikes which are usually very accurate with their trip readings and seem to be around + 1.5% error.

Fuel consumption error of +18% was a real surprise, so my frugal fuel consumption figures of 29 km/l were all crap and a much more realistic figure of around 24 km/l fuel consumption were calculated.

The surprise figure here is the fuel range error of +5%, surprising because I would use use total fuel (14 litres) multiplied by fuel use (which is +18% high) to arrive at the fuel range but the fuel range is only +5% high so obviously KTM have deliberately set the fuel use figure high to make the motor appear very lean and frugal - which it isn't.


BTW my 790 is a July 2018 model with around 9,000 kms running Pirelli Angel GT tyres approx 30% worn and software version 0.17 (soon to be updated)
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Interesting figures! I haven't checked the speedo over a wide range against my GPS to see if it's linear but at the NZ legal open road speed limit of 100 km/hr, it pretty much matches your data, showing 105-106 km/hr. My GSX-S 1000 showed 108 km/hr. I haven't checked accuracy of the fuel consumption figures. From the "fuel remaining" readout, it indicates that I should be able to get close to 300 km (minus 5%!) But I'm not game to push my luck.

I'm heading out today for a couple of hours. Might try and collect some decent data.
Thats interesting, up to 300 km range for you, I must be easier on the throttle because my instrument range is typically 340 - 350 kms indicated.
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Ok, here are my readings from a 170 km round trip this morning. Bike instrumentation compared against my Garmin GPS.

Speedometer: 5% more than GPS. Percentage looks pretty linear from readings either side of the open road speed limit.

Odometer/trip: 6.6% more than GPS. The route was pretty twisty and whether the lean angles (smaller effective diameter) for much of it had any bearing, I don't know.

Fuel consumption: Bike instrumentation shows 8.9% better fuel consumption than the GPS mileage divided by the actual fuel taken to top up the tank. Fuel consumption with a mix of Street and Sport mode riding was 4.61 km/100km. This looks about right for the 300km range I reckon I get on an average open road run without hammering it all the while.

I'm running NZ 95 octane fuel, the bike has covered ~2000 km and is on the OEM tyres.

I'll repeat the exercise in another 1000 km.

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Interesting, your fuel consumption is 8.9% error compared to my 18% error so looks like a fault with my bike, maybe a fuel flow sensor.
Will be getting a software update after Easter so will talk to the dealer.
Thanks for going out and checking my readings, much appreciated
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Interesting, your fuel consumption is 8.9% error compared to my 18% error so looks like a fault with my bike, maybe a fuel flow sensor.
Will be getting a software update after Easter so will talk to the dealer.
Thanks for going out and checking my readings, much appreciated
No worries - another local 790 owner who isn't a member of this forum said that he gets close to 300 km range when he's in cruise mode rather than hustling. Incidentally, my gauge never shows more than 300 km range even with the tank absolutely brimming.
Same here, but its funny how it sometimes shows over 800km just after tanking/ before ridingXD. Wishful thinking:)
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Was a nice warm autumn night (20c) on Sat so thought I would go for the 790's first night ride since I bought it.
Stupid instruments said I was getting almost 35 kpl and my range was 380 kms doing 110 kph on the freeway - what the f**** how can I tour when my instruments are so obviously inaccurate.
Discovered something else, the headlight is an absolute joke on both high and low beam AFTER I realigned the beam. Pretty piss poor when you consider the price of this bike and the headlight being LED's, my $20 torch gives better output.
Definitely sounds like you have a fuel reading issue. Mine doesn't go past 300 when full (after getting on the move).

Have only ridden in the dusk so far but the reports about the lights on YouTube have been quite complimentary. I must take it out after dark and check mine.
Done a few Kms at night on mine now (not by choice) and have no complaints about the lights. I guess it's a matter of what you are used to.
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This YouTube video will explain, the first few minutes show the bike ridden at night, at first it looks like the lights are OK but if you look closely the lights are actually fixed freeway lighting and not the 790's lights, the 790's lights are almost invisible, in one section he passes a bus and you cannot see his lights (around 1:30).


Maybe it is the colour of our roads and terrain or something but the lights just don't seem penetrate, its a bit like the colour temp of the LEDs is too low a frequency and it should be more towards the white end of the spectrum. Its a real problem here in Australia where we have a kangaroo plague and roos have come into the city and can be on the roads as close as 10 kms from the centre of Melbourne (population 5 million).


If you want to know what good headlights are like then ride a Honda.
Done a few Kms at night on mine now (not by choice) and have no complaints about the lights. I guess it's a matter of what you are used to.
I run in the dark in the mornings on the way to work and have been out late in the evenings to test the headlight. I tend to agree with you KW, though I must say the first night ride out I brought a driver to adjust the light, which I had to by A LOT! Brought the low beam up about as high as the factory set the high beam, if not higher. I do find that coming around a sweeper, I have to use the high beam otherwise I can't see my line and riding blind like that scares the $*&^ out of me! Now that I adjusted it, I feel like a tad higher and I would be set with the low beam, but that pretty much makes the high beam illuminate the tree canopies!
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Well, out of curiosity, I went out on the 790 tonight to do my first ride in the pitch black. A local twisty hill road with no lighting, then a long straight – also with no lighting. Dip and main beam were set up pretty well and need little or no adjustment. Forward illumination was sufficient to be able to cruise on the straight at the open road speed limit (100 km/hr). On the twisty stuff, forward lighting was again adequate but what I really liked was the side illumination where verges were well lit. I wasn’t expecting that.

Trying to make a comparison, forward illumination is about the same as my Honda Blackbird before I fitted higher wattage bulbs. Side illumination is better than the ‘bird, which has a sharp cutoff because of the reflector design. Forward illumination isn’t as good as my GSX-S 1000 as I fitted a high performance Xenon bulb from the get go. Side illumination is better for the same reason as the Blackbird. Forward and side performance are about the same as my twin round headlight Street Triple which had upgraded Xenon bulbs.

I’ve done 5 of the NZ equivalent of the Iron Butt 1600 km in under 24 hours organised rides on several different bikes (called the Rusty Nuts Grand Challenge in NZ). 11 or 12 hours of those rides are in darkness on mainly back roads. I’d have no problem on doing one on the KTM.

Nothing in NZ that would eat your face if you ran into it at night but wandering sheep, cows or deer are going to sting a bit if you collect one. :smile:

Just out of interest, one of the testers on YouTube singles the lighting out for particular praise:

1 minute 55 seconds into the video:

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I thank you for the information - I would add that my 1290 Super Duke R had a speedo error (high) of at LEAST 12%!!! If I were riding 100Km in a 100Km speed zone cars would be passing me left and right - and I/m talking about grandma in her Prius or Fiat coupe - There was no way to fix it -
Moreover, as for "range" right after I bought the bike the low fuel light came on and it read 30 miles remains - within a mile or so I ran out of gas on the freeway - there I am side of the road - A State Patrol officer came by and gave me a gallon of gas -

Consequently, I consider the 790 spot on by comparison - I always start looking for fuel at 100 miles of 160 Km to be on the safe side -
BTW if those are the only complaints I'll take them as I like this bike a lot
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Man if you guys are getting 300 + Km on a tank of gas you're riding a lot smoother slower and easier than I am - I do live in twisty country and love getting on the bike but I/m happy if I get 250 KM and start looking long before that - my low fuel light came on at 175 yesterday - I happened to be right in front of a service station - I put 3 GALLONS or, 11. 6 liters - - I really don't care what kind of mileage I get as long as I know as I love this bike so mileage doesn't matter
Man if you guys are getting 300 + Km on a tank of gas you're riding a lot smoother slower and easier than I am - I do live in twisty country and love getting on the bike but I/m happy if I get 250 KM and start looking long before that - my low fuel light came on at 175 yesterday - I happened to be right in front of a service station - I put 3 GALLONS or, 11. 6 liters - - I really don't care what kind of mileage I get as long as I know as I love this bike so mileage doesn't matter
1 US gallon = 0.832674 Imperial gallon. Reckon that's the reason? Only pulling your leg. Some days, I'm sweating at the mid-250's but if it's not getting hammered, it makes a big difference
I’ve done 5 of the NZ equivalent of the Iron Butt 1600 km in under 24 hours organised rides on several different bikes (called the Rusty Nuts Grand Challenge in NZ). 11 or 12 hours of those rides are in darkness on mainly back roads.
Wow Geoff! Those Iron Butt challenges are no joke, pretty amazing that you saw all those through, not sure I could pull that off, haha.
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Wow Geoff! Those Iron Butt challenges are no joke, pretty amazing that you saw all those through, not sure I could pull that off, haha.
Thanks Kelevra! In NZ, they mainly take place over twisty back roads one day in October. They start at 3pm, so there are less than 5 hours of daylight after starting. It's a mental challenge as much as physical. Have also done the Southern Cross. That covers around 4000 km in 5 days round both major islands of NZ. Good fun at the time but too old for it now!
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Visited the dealer today for some software updates, turned out my software was way out of date (0.17 -> 1.0), 3 updates behind actually, also had some sort of flash upgrade to the fuel injection system and 3 TI's (KTM's version of a recall, technical instruction ??) done, not sure what, and 3 more to do with parts on order. The 3 TI's to be done apparently are a new airbox lid and 4x rear sub frame bolts, not sure about the other one, dealer seemed real reluctant to elaborate, very odd.

Bike is definitely different, idles higher, shutting the throttle doesn't immediately slow the revs, bike "seems" to have more power, range and fuel consumption figures are still high but the error seems to be less, bike definitely felt different for the 1st 50 kms after which I just got used to the new feel.

My bike was one of the 1st Australian bike sold mid 2018 so probably explains why my earlier comments were so different to riders with newer bikes.

Like Geoff I also do the odd long ride with FarRiders in Oz, with lots of night time kms travelled on my KTM 1050 and roos in plaque proportions hence my obsession with good lights. Now that I think about it the night I checked the lights was a bright full moon so the contrast of the lights may have been less giving less penetration.
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Must say that I've been impressed with the 790 lights. Compared to my Triumph Tiger commuter they are miles better and compared to my old Ducati 900SS they are space age!!
@Geoff - You live in a lovely part of the world, I'd love to ride the Kopu- Hikuai on a 790.
I first did it on an old GSX750 back in 1988 while I was visiting my Brother. I turned around before Tairua and did it again! Part of the reason I ended up staying there for 8 years!
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