Gen III Engine Temp / Low Ambient Temps

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d in the d

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Hi All,

I've done a bit of searching but have not found if anyone else has encountered this. Since this is my first few hundred miles this last weekend I saw some "interesting" things on the engine temp readouts.

The stats

  • Under 200 miles on the clock.
  • Ambient temps were low 40's
  • Engine temps were cycling between 150ºF and 180ºF within 30 seconds to 1 minute.
  • At first I thought it was a slug of hot water recycling through the cooling loop that may have been generated at a stop light. The temp cycling never did go away until the ambient temp rose above 55ºF. After that, engine temps seemed to hover normally with no spikes.

My thinking is that at lower ambient temps, an opening of the thermostat causes a huge thermal transfer from coolant to outdoor air.

I'm sure the engineer's designed and tuned to cooling system to work best at typical riding temperatures of 55ºF and above.

I'm sure that such immediate real time data that the temperature sensor readout provides is info overload and should not be a concern since the temps changed very fast. I am sure that the engine overheating concern during break in is for sustained high engine temperatures and not for anomalies like this.

  • My question is, am I correct in assuming that this is normal - keep riding it!
or

  • Do I take it in for a warranty service for a sticky thermostat.

If anyone would care to chime in, I would appreciate your feedback.

 
That is normal operation:

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I noticed the same condition on my 2013 a couple of days ago. I was somewhat amused for a short time then changed the readout to miles and forgot about it.

 
Thank you gents,

I did do a search looking to see if it had already been discussed, perhaps I used the wrong search terms.

Didn't want my first real post to be worthy of NEPRT. Guess I blew that one.
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If you think about it, the temp sensor is only reporting the coolant temp right? So it would make sense that it would fluctuate as the thermostat cycles until the entire volume of coolant is warmer. In cold weather coolant in the radiator is going to be super cooled, so that would be why you'd see the swings on the gauge. I'm sure that the actual metal of the engine doesn't fluctuate that quickly or wildly.

 
This is my first digital coolant temperature. I think it's too much information. I kind of liked my graphic temp gauge on the 06, didn't make me as worried. Especially when it's really hot (105+) in traffic and the coolant is reaching 222 at times. So I just ride it and think my 06 did the same thing and I just didn't know the degrees.

 
The GenII was digital too in reality........ sounds like they should have programmed delays in the readout so you didn't see every little fluctuation.... why not switch the display to something else........

 
Thank you gents,
I did do a search looking to see if it had already been discussed, perhaps I used the wrong search terms.

Didn't want my first real post to be worthy of NEPRT. Guess I blew that one.
blushing.gif
Don't sweat it man... The search engine here suks hot sweaty cats nutz.

Next time use google... FJR Forum "topic"

Or just hit our next tech weekend and be smarter than anybody here except me!

 
As an aside, the only bike that I've ever owned with a digital readout of the engine temps was a 1998 VFR800 (my son now owns it), and I recall that the coolant temp gauge was the cause of constant consternation for new ViFfeR riders. Many of the "old sages" would tell the "newbs" to just switch the gauge to display ambient air temps and not worry about the coolant temp until you started seeing the coolant spurt out on the ground.
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Just today I was travelling through the streets of our town with numerous stops (over a period of a half hour or so) and noticed that the temperature readout was up to 110 degrees C or more at times, which I hadn't ever noticed before (2013 FJR). The temperature dropped slightly when I got out of the town area but then jumped wildly over a range of approximately 20 degree C or so. That too, I had never noticed before.
The air temperature was in the 10 - 13 degrees C range.
Does this behavior seem normal or should I be looking into this further?
Thanks in advance for any ideas and information.

 
^^^^^ (up three posts)

Holy shit! Did Bust reassure a noob that it was OK to ask before googling? And then explain how it is done?!?! Something must be wrong with the forum software ........

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With sincere respect: My 2 cents (exchanged into loonies for my new Nova Scotian friend, Dale2010) is that internal combustion engines need to run at high temps, and require pressurized cooling systems that allow them to operate well above the boiling point. Our portable nuke plant (SSN 682 -- mentioned for Veterans Day) ran coolant temps within a few degrees of 480F, and was pressurized like an accountant at tax time.

You should expect your coolant temp to drop once out of town, with the higher volume of cooling air passing through the radiator. When stopped at a red light, there's very little cooling air passing through the radiator, so its ability to cool the coolant is significantly reduced. Coolant temp varies, and it's no big deal.

As long as she stays within the temp range called out in the Canadian Owner's Manual, you should devote your attention to flower-sniffing or whatever else one does in the Maritimes in November.

 
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Might be an accountant, you never know, although he looks like Mr. Spock with a goatee.

 
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^^^^^ (up three posts)
Holy shit! Did Bust reassure a noob that it was OK to ask before googling? And then explain how it is done?!?! Something must be wrong with the forum software ........

------------------------------------

With sincere respect: My 2 cents (exchanged into loonies for my new Nova Scotian friend, Dale2010) is that internal combustion engines need to run at high temps, and require pressurized cooling systems that allow them to operate well above the boiling point. Our portable nuke plant (SSN 682 -- mentioned for Veterans Day) ran coolant temps within a few degrees of 480F, and was pressurized like an accountant at tax time.

You should expect your coolant temp to drop once out of town, with the higher volume of cooling air passing through the radiator. When stopped at a red light, there's very little cooling air passing through the radiator, so it's ability to cool the coolant is significantly reduced. Coolant temp varies, and it's no big deal.

As long as she stays within the temp range called out in the Canadian Owner's Manual, you should devote your attention to flower-sniffing or whatever else one does in the Maritimes in November.
Happy Veterans Day you "nuke bubble head", by the way do you guys really glow in the dark? Thanks for serving our great Nation!

 
Thanks Uncle Hud for the reply and information. It's good to know that these readings are well within the normal limits.

Neither the owner's manual nor the service manual suggest much beyond, "if the engine is overheating..." Other than temperatures at which the thermostat should open and close, there is no other mention that I can find (in the service manual).

The reason for my concern at this point is that I've never noticed the temperature gauge acting like this before (so erratically). Usually, the temperature readings might rise to the 90s but then drop smoothly back to the 60 to 80 degree C range and stay there. Never have I previously noticed it wildly jumping back and forth, thus making me wonder it this is a normal response to stop and go conditions in cooler weather.
In the heat of the summer, under similar conditions, the movements seemed much less erratic, for whatever reason.
Regards from the rapidly cooling N.S.

 
If it used to vary smoothly, and now varies wildly, you may have a 'funky' thermostat that has trouble opening and closing as per spec.

Sorry, but there's no "normal temp range" listed in the US Owner's Manual either.

 
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