Another place to put the ambient temperature sensor

AMBBWM

Getting there...
Location
Tennessee
My BMW GS has one of these as well and the temp is usually spot on. It is located the the front of the bike under the dash and does not receive engine heat. With this in mind, I decided to find a place in the front of the REH somewhat protected yet away from the engine.

I found a spot that fit the bill. Took about an hour to do, only because I soldered and heat shrinked the wiring and then ran it through some plastic tubing to protect it under the tank.

Took it for a spin around the block, and happy to say, it was within a couple degrees of what my phone gave as the local temp. 81°. Usually on a cool day like today, still around 100° or more. I call it a win.

Will be anxious to see how it works out on a hot day. This I do know, moving, it will not be picking up engine heat.


temp sensor.jpg
 

Bradster49

Well travelled
Location
Lille France
Nice, very nice.
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My BMW GS has one of these as well and the temp is usually spot on. It is located the the front of the bike under the dash and does not receive engine heat. With this in mind, I decided to find a place in the front of the REH somewhat protected yet away from the engine.

I found a spot that fit the bill. Took about an hour to do, only because I soldered and heat shrinked the wiring and then ran it through some plastic tubing to protect it under the tank.

Took it for a spin around the block, and happy to say, it was within a couple degrees of what my phone gave as the local temp. 81°. Usually on a cool day like today, still around 100° or more. I call it a win.

Will be anxious to see how it works out on a hot day. This I do know, moving, it will not be picking up engine heat.


View attachment 505
I like it ! thanks for posting
 

AMBBWM

Getting there...
Location
Tennessee
I relocated my sensor to the rear of the bike, under the rear tail lamp assembly. It still indicates roughly 10F over the actual temperature. Any ideas?
Still trying to get a feel for where the gage will actually read. It is close, based on a ride then getting in my car and seeing what it was reporting. The results were very close. I do have a friend that has a Honda African Twin, and his sensor always reads 5° higher. Could be the REH will do the same, but if it is consistent, at least it will be better than the 100° plus it seemed to always show.

Once I get more seat time, I will report back .
 

NewEnglandHimalayan

Well travelled
Location
New England
The one in my bike seems to read fairly close to ambient despite being in the stock location. Maybe up to 7 degrees F higher. The one in my car is always within one degree from what the weather man in the radio reports.
 

Sidequestadventure

Finally made it
Location
SF Bay Area
This is likely to soak, it would be similar putting it on the dash of your car just with the windows down. UV by itself is going to give you a false positive. Flipping that 180 degrees is probably far more accurate.

The guy who stuck his in the rear box has a similar problem in that the location and application will soak but won't react very quickly, thus not being anywhere near accurate unless you only use it in the same condition over and over.
 

ScotchmanDR

Finally made it
Location
SE Michigan
How do I remove the Ambient Air Temp Sensor to relocate (just pull)? That's why I'm asking first

I read somewhere that it may be part of the info used by the ECU for EFI so moving it (changing the temp) should make the ECU more accurate? Note: Ok maybe not! I only read it ;-)
 
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CarstenB

Well travelled
Location
h-town tx
just wiggle it carefully out of the rubber grommet. I didn't notice any effect on how the bike is running after relocating the sensor. Not sure if the ambient temperature really is used by the ECU or just the engine temperature (which is a separate sensor).
 

Sidequestadventure

Finally made it
Location
SF Bay Area
What let you to this conclusion. I'm not doubting you but in a simple ECU engine temp isn't always a consideration. However if it is, it would be very important to know.
The US version uses a 4 wire (or 5?) o2 sensor which I believe carriers exhaust temp which would be required for emissions and can be used to adjust.


How do I remove the Ambient Air Temp Sensor to relocate (just pull)? That's why I'm asking first

It appears to be part of the info used by the ECU for EFI do moving it (changing the temp) should make the ECU more accurate?
 

ScotchmanDR

Finally made it
Location
SE Michigan
Ok thanks all. Just asking before breaking anything lol. Moved it to the "document" box. Minimal plastic carving and no wire snipping. Dropped the thermometer reading from 117F to 98F when riding. Cold-Start temp was 92F which is close to the sunny temp here. Shade temp was 88F but the weathermen (and "Google") keep saying it 85F. No Way!

So a fairly accurate reading on cold startup. Riding temp is then the Saddle Temp and something I can live with.

Anywhere it goes, it is going to have some variation of convection from the engine or just the slipstream.

I'll take a saddle-temp over an almost-useless engine-airflow-temp anytime!

Another happy mod...
 
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AMBBWM

Getting there...
Location
Tennessee
I have had absolutely no issues after making this move. After a few weeks, it appears the temp always reads about 10°F higher than the Weather channel for the area, just like Kokomotos'. As I said earlier my buddies African Twin is always 5°F higher though my Beemer is spot on. Subtracting 10° from what I see on the readout is easy enough and gets me within a degree or two. Not critical information, but nice to know.
 

MrDralas

Well travelled
Location
Planet Earth
919ED927-65FC-44C2-B4AA-BDDE6205CCF6.jpeg

The bike has 2 “air temperature sensors”. The ambient temp sensor that people are moving circled in red only feeds into the instrument cluster. There’s a second on for the engine circled in green which feeds in to the ecm and allows for the engine to adjust fueling accordingly to the intake air temperature. So moving the one circled in red, would have no affect on the runnings of the bike. The one in green would be buried some where’s not easy for people to pick at, probably inside the intake some where’s so it can read the stream of air going in to the engine.

Hopefully this helps answer someone worry about this

How do I remove the Ambient Air Temp Sensor to relocate (just pull)? That's why I'm asking first

I read somewhere that it may be part of the info used by the ECU for EFI so moving it (changing the temp) should make the ECU more accurate? Note: Ok maybe not! I only read it ;-)
The engine doesn’t really care what the outside temperature is in almost any vehicle (I say almost any because newer cars might limit power if icy out, they’d used the ambient temp to know if icy), it cares about the intake air temperature. The engine will always heat the air up that’s coming in to an engine, if it looked at ambient (correct ambient) and not the air temp inside the intake it would over fuel the engine and run rich.

What let you to this conclusion. I'm not doubting you but in a simple ECU engine temp isn't always a consideration. However if it is, it would be very important to know.
The US version uses a 4 wire (or 5?) o2 sensor which I believe carriers exhaust temp which would be required for emissions and can be used to adjust.
The ecm does use engine temperature it’s 2 to the left from the green circle, I think most fuel injection vehicles do for proper fuelling. The o2 sensor looks like a 4 wire one, so 2 for a heater circuit to warm the sensor up (wake it up, they only work warm) and 2 wires to measure the oxygen in the exhaust so it can adjust by adding or removing fuel to get whatever ratio it wants.
 
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