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Discussion Starter #1
Does anyone know what the temperatures are for the bars? In other words....


1 Bar = __ degrees
2 Bar = __ degrees
3 Bar = __ degrees
4 Bar = __ degrees
5 Bar = __ degrees
6 Bar = __ degrees
7 Bar = __ degrees

8 Bar = __ degrees
 

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Manual states the following



8 bars would be 120C, not sure about the others

I’ve hit this once in London when it was 39C, combined with my coolant leak and heavy traffic, pulled over immediately and shut the bike down to let it cool off.

I explained this to the dealer and said that I was concerned that something may have happened internally. Apparently he’s been working with KTM’s for nearly 25 years and didn’t seem worried at all, he just smiled and said you’d be surprised at how hot they can run.
 

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I personally wouldn't find that terrible reassuring, haha.
At the time I wasn’t sure if that made me feel better or worse to be honest.

However they’ve found and fixed the problem in half a day, this has been going on for months with the previous dealer, infuriating as it was something so simple.

Fingers crossed it doesn’t happen again.

My old man is a diesel mech engineer and actually told me the same thing, he said with modern machining and materials it has to get extremely hot for long periods of time before it starts breaking things and the manufacturers will usually set the alert thresholds much lower than that anyway.

I on the other hand am mechanically inept :grin:
 

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I not often saw My Duke above 4 Bars, When the Fifth bar appears the fan still run.


On my Z750 the fan began to work at 106°C and stop at 96°C but it was the engine temperature on the digital instrumentation not the coolant liquid temperature;
I ask myself how take the engine temperature on the duke ?

I don't want to read IYA In Your Ass :grin:
 

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At the time I wasn’t sure if that made me feel better or worse to be honest.
hahaha, I'm sorry..


My '06 Husky SMR510 didn't come with a fan, PO had one installed with a switch, I had that switch on, more often than not, but I wasn't being too gentle with the bike..
 

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I bet we could figure out a good approximation of the temperatures using a handheld "laser dot" thermometer pointing at the coolant header going into the tank - at least for the first 4 or 5 bars or so.

I think it might be difficult to get it go much higher while stationary on closed throttle doing nothing - but it could heat soak higher.

Something to try when someone's got an hour to kill on a weekend?
 

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Discussion Starter #9
Yea, I have the manual also! I am looking for engine temps just to compare. My old bike was flashing as overheating at 259 degrees F. Curious as to what the KTM parameters are for their bars. If anyone finds it anywhere, please post up!
 

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@Chic - I actually intend to do this. I have a reasonably accurate infra-red laser thermometer that I can calibrate for different materials - I just haven't had the time as yet.
 

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Discussion Starter #11
No rush brother! I would love to have the time to do this myself. I have to get my laser working right first though. It would be nice if KTM had this info just for knowledge.
 

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Yea, I have the manual also! I am looking for engine temps just to compare. My old bike was flashing as overheating at 259 degrees F. Curious as to what the KTM parameters are for their bars. If anyone finds it anywhere, please post up!
The manual says 120C (248F) emergency operation activates, so not far off that.

If the top end of 8 is 120C should be fairly easy to reverse the scale (keeping in mind these would be the top end values of each number)

0-3 = dunno
4 = 45-59
5 = 60-74
6 = 75-89
7 = 90-104
8 = 105-119
9 = 120 WARNING

Logically that seems about right, interested to see what the laser says.

* terms and conditions apply - this is purely conjecture

** edited guess table cos I feel dumb
 

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Ambient is variable according to climate so suspect it's not considered directly, though I do imagine the scale is offset and not just from 0 / 32 degrees upwards.

Fluid temperature sensors are usually thermistors - a resistance that changes with temperature. The resistance is implied from voltage drop then quantised - that is, it's measured and turned into numbers and interpreted via some formula. The base (offset) and scale (rate of change of resistance with temperature) being set for a particular device/application.

I did consider guessing like this but after reading the manual I think there are 10 levels from 8 bars.

The first is no bars showing, then in sequence 1-8 bars ... then the manual differentiates between 8 (hot) and 8 flashing (too hot!)

I think the 8 flashing is the when emergency protection measures are taken (120 Celsius is mentioned in the manual) - I think this mean reduced power via the ECU.

Anyway, I will try to find some time to actually measure this over the weekend.
 

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Like I said just guessing, in the past I’ve been told warming up is usually up to around 55C (131F) which seems to be around 2-3 bars operating temp 55-100C which would be 4-7 and hot is usually over 110C+ 8. Which kind of seems to align.

There’s people here much smarter and who know way more about this than I do about all this :grin: but you are right 0 =/= 0C on the lower end, again I would assume there’s a short period of time where it’s calculating what it thinks the overall temp is.
 

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Owl, I may be missing something but wouldn't 0 bars be ambient temperature?
Nope - but it wont be 0 either.

The 4-5 bars split will be about 95-105°C, at a guess, as that is where (on mine) the fans seem to switch - Yes Celcius. Not Fahrenheit.

The only way to "know" is

Crack the CPU and look.
Ask KTM
Verify with alternative measurement.

And I'll be frank here - I am not all that convinced that some of the KTM electronics are all that great. So I'd not bet that they all read the same.

If you're worried about overheating - there is an option (potentially) to use a higher pressure radiator cap. I have not looked to see what is fitted yet.
 

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To be honest I would never have even thought twice about any of this until I saw this thread, but I am intrigued now :grin:

Also found in the manual

The operating temperature is reached when 5 bars of the temperature indicator light up.
Whatever the operating temp is, again it doesn’t say.

And this regarding launch control

Coolant temperature: > 60 °C (> 140 °F)
Not a huge help.

This is interesting though

Coolant temperature ≤ 35 °C (≤ 95 °F) - The shift warning light always lights up at 6,500 rpm
Look forward to see what @dma ‘s results look like from the laser.
 

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Discussion Starter #18
Yes!! Now we are getting into it!

The basis of my question was really just to compare to my old bikes op temps. I was running typically at about 160-180 while riding, and hot was around 180-205 or so (all F). Once I put in the Engine Ice, it drove those operating temps down about 15-20 degrees F. If Owl's original guestimate was close, the KTM runs super cool compared. I would think 5 bars is somewhere around the 180 deg F mark.

The stuff from the manual is rather confusing. The first couple of times I read through it I was wondering how the **** I know the temp of the coolant and how that compares to the temp the bike is showing. Very interested in DMAs results!
 

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This is interesting though

Coolant temperature ≤ 35 °C (≤ 95 °F) - The shift warning light always lights up at 6,500 rpm
Like I said - mine is all just guess work *terms and conditions apply

Just took her out for a spin after riding for a bit (still no bars) rev’d just up to 6.5k and the shift warning popped up, after a few more minutes 1 bar popped up and tried again, no shift warning, that would seem to indicate that 1 bar is at least 35C (95F), so my lower end of the scale is definitely off then.

On the bright side coolant leak appears to be gone - bike seems to be sitting at a constant 5 bars even with a bit of ‘spirited’ riding :devil:
 

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Discussion Starter #20
Like I said - mine is all just guess work *terms and conditions apply

Just took her out for a spin after riding for a bit (still no bars) rev’d just up to 6.5k and the shift warning popped up, after a few more minutes 1 bar popped up and tried again, no shift warning, that would seem to indicate that 1 bar is at least 35C (95F), so my lower end of the scale is definitely off then.

On the bright side coolant leak appears to be gone - bike seems to be sitting at a constant 5 bars even with a bit of ‘spirited’ riding :devil:
Nice job on figuring that out. If one bar is about 35/95+/-, should be able to pull the rest of the numbers. I'd be interested to see how this equates to what DMA pulls. I don't care what they say about you Owl.....:grin:
 
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