Ambiant tempurature display?

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I agree with Fred. You want to know when water turns to ice to make necessary adjustments to your riding behavior. Mine reads 2 to 3 degrees F too high as well. Other than that, I'm not too concerned about what the temperature is.

 
The street signs at banks and such are generally not accurate, probably for the same reason as our bikes - sensor location. I've also seen several have vastly different readings in one particular area.

 
Consider as well that the temperature a few feet from the pavement could very well be a couple of degrees higher than the temperature wherever that sign's sensor is. Maybe they're both right -- or wrong.

 
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lots say the bike is wrong, compared to what ??
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couldn't figure how to edit my post.

 
I also correlate the temp to weather reports but then again I get them off the internet so they must be right.

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I also correlate the temp to weather reports but then again I get them off the internet so they must be right.
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So true.

I live in a rural area, and back when I still earned an honest living, I'd have to scrape ice off my windshield and there would be a glaze of ice on puddles outside when my phone said it was in the upper 30s. Even my thermostat inside the house would list the outside temp in the upper 30s, but there would be the ice. Go figger ;)

In Formula One, they'll often give the track temperature and ambient temperature, and they'll be 30 or 40 degrees apart. I would imagine that applies to any paved surface. The road may be 100 degrees, but the air above a grassy field next to it could be, say, 80. Maybe the air temp 4 feet above the road would be between the two. What's the right temperature right there?

And a cold winter morning there may still be ice on the road in the shade or on bridges when the air temp is in the mid 30s. I know I've hit ice in my pickup when my dash thermometer read 35 degrees.

 
The reason there is ice at 37 F is radiation heat transfer.

Pavement is similar to a "black body". It can radiate away its energy to another colder black body, like the nighttime sky, or deep shade.

There is also the phenomenon of thermal inertia. That's what's in play when bridges freeze first. The ground is a thermal reservoir, slowing the cooling rate for pavement. But there is no ground directly in contact with the underside of a bridge.

FWIW, the water freezes around 32F, and so even if the air is at 37, if the pavement is 32, moisture on the pavement will freeze. The air does not have to be 32 for there to be ice forming on unsalted pavement.

 
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Mine seems pretty close after you get some air moving.

Guess if you really wanted, you could trim the sensor with a precision resistor.

 
If you're cutting it so close that you're relying on the temp display to keep from crashing, you should probably take the cage. Mine is close enough to give me a rough idea. That's all I've ever needed. Never tested it to determine how accurate it is.

 
... says the guy from the frigid southwest. Some people won't ride in rain either. :rolleyes:

Certainly not relying on the temp display to "keep me from crashing". Just using it, as you suggest, as datum to avoid those kinds of situations. And it is close enough for that. Heck, my old '05 or the even older ManStrom don't even have a temp displays and that's never kept me from riding it into a little light snow. Though, when the roads are icy that's a whole n'other thing.

 
I just look at it as if my bike is wearing a hat, misdjudging the temp a bit on the high side. I ride below freezing fairly frequently in the winter. It's nice to know how close to the forecasted temp it really is where you're riding. Also nice to note a quick drop as an alert to hitting a front, where I might not notice in full gear.

 
So I have the thermostat telling me it is 50 degrees in the garage. I grabbed another digital thermometer from inside the house That said 49.6 degrees. The 2015 bike is registering 50 degrees sitting there also. So with no movement they all seem to be pretty close. Yesterday I bought a digital thermometer at Wally-world that I will stick on the bike. Then I will check to see if there is a difference traveling down the road. That will tell me if the bike is picking up some sort of engine heat and maybe I can create a barrier if needed to have it read correctly. Assuming I can find the sensor which I believe I know where it is on the Gen2 at least. Hopefully it is the same on the Gen3.

Stay tuned,

Dave

 
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... Assuming I can find the sensor which I believe I know where it is on the Gen2 at least. Hopefully it is the same on the Gen3.
Stay tuned,

Dave
Sorry, it's in a different place on the Gen3.

If you look at this picture, taken during removal of the front cowling (a bear of a job):

(Click on image for the original)



Find the label stuck to the underside of the instrument unit. Just below it is a wire ending in a connector, connecting to what I believe to be the ambient temperature sensor. Unlike the Gen 2 sensor, this is a bolted down moulded plastic thingy.

This is it, with its nut and bolt, as I removed it from my broken mirror mounting frame.



 
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Has anyone tested the Gen III temp display for lowest possible temp reading? I know that the Gen II bottoms out at 16 degrees, even if the ambient temp is colder:

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It was at least down to 12 degrees when this was taken along the Puyallup river (Glacier fed river from Mt Rainier). Between the cold water and the tendency for cold air to sink to the bottom of the valley, my ride along this rural road in the morning is always the coldest part of the ride. I did set a record last week for temp swings because it was 24 according to my 07 temp gauge as I rode along the river and then a mere 5 miles away along a major highway in that same valley it was up to 39. I felt soo warm (relatively) that I had to turn down the heated liner. :)

 
Has anyone tested the Gen III temp display for lowest possible temp reading? I know that the Gen II bottoms out at 16 degrees, even if the ambient temp is colder:...
My Gen 3 (UK) Owner's Manual says -9C to 50C, which would correspond to 15.8F to 122F.

 
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