[Wingdreamer]

At one time, Honda had a temp gauge that actually showed you the true temp that your engine runs at... THEY didn't like the truth, so they got our Wings back in and installed an in-line harness that totally misleads the driver into thinking that the engine will NEVER run hotter than just below 1/2 way. As a matter of fact, no matter what the temp is outside, my bike has NEVER even touched the 1/2 way point on the gauge (even in extreme heat, while stuck in traffic and the fans running full out). I just want to remove the Honda upgrade that modifies this so that I can see the true engine temp. I have looked several times in the left pocket for the in-line harness and haven't been able to find it. Anyone have any pics of this harness, and where it plugs in at each end?

 

[wingnutzz]

Actually, all of the 1800 temp gauges have always operated this way. The new harness that they installed just changed it so that it did not respond so rapidly and early to the temperature changes. My 2002 has always operated this way, and yes, before the new harness and afterwards I can make it climb when I am climbing a steep hill at speeds around 15-25mph where lots of heat is generated by the engine, little air is flowing across the radiators, and you are above the 15mph where the fans kick off. A little speed, engine, and transmission control lets me get through this the rare times when it happens.

 

[Joe In Calif]

Here is the service bulletin with the instructions.
http://www.ridersrally.com/sb/sb01.pdf
My 02 had the temp gauge update and I also could make it go up way past 1/2 way in the right conditions. You could always add an after market temp gauge if you want to.

 

[LarryM]

Considering that there are no temp markings on the temp gauge, I don't see how you could possibly know what the true temperature is before or after the update.

You are going to be a bit disappointed if you remove the update harness. Your bike's gauge was non linear before the update too. The only thing the harness does is correct a calibration problem that caused the needle to indicate that the bike was running hotter than it actually was. The needle could go into the red when the bike wasn't even overheating. If you remove the harness, you will throw off the calibration.

The non linear curve is built into the temperature sensor that is bolted into the engine block. There isn't anything you can do to alter it. Even if you could, all you would get is a needle constantly moving up and down. You still wouldn't know what the temperature is.

As far as I know, there has not been a mass production car or motorcycle made in the past 30 years, (probably longer) that has a linear temp gauge from the factory. If you want that type of gauge, you will have to install an aftermarket racing gauge.

 

[Stan Wright]

The harness you are looking for is forward of the left storage pocket. The harness has green connectors, is about 12" long, and is nothing but wires except for one line that has a component in it.

But like the other guys have said, the gauge has always been non-linear. Mine has the update and still shows hot when the bike is hot.

 

[Farmguy]

By definition all thermostats help make the cooling system 'non-linear'.

Lightly load the engine, the thermostat reduces coolant flow, add load to the engine the thermostat permmits greater flow.

The only time the load - temp relatiionship is linear is when it is hot enough that the thermostat is wide open.

At 'normal' operating temperature the thermostat changes the flow so the temp does not change -- this characteristic causes many to assume the gauge is non-linear.

 

[Wingdreamer]

As far as I know, there has not been a mass production car or motorcycle made in the past 30 years, (probably longer) that has a linear temp gauge from the factory. If you want that type of gauge, you will have to install an aftermarket racing gauge.[/QUOTE]

Larry, even my 2004 Montana's temp gauge (which normally sits just below the 1/2 way mark at operating temp), will creep up when I'm pulling my trailer up hill on a hot day. I'm telling you, the needle on the temp gauge on the Wing has NEVER (did I say NEVER?) moved above the "just below 1/2 way mark" ever on my Wing in FIVE years of riding. I have ridden the Wing in some extreme heat, low speed riding, parade riding etc, and its never moved. I don't define that as normal..... but I do define it as unnerving!:? C'mon.... the gauge has to move once in a while!!!!! (or is it only at meltdown.... no warning... too late at that point...)

 

[GoldWingrGreg]

Todays temp gauges go through a voltage limiter. Just like a gas gauge does. No one want to see the splashed readings of a tank half full. If a gas gauge did not go through one, we would see a gas gauge drop to empty during take off and over full during braking. So a reading is taken every so many seconds and that reading is "pulsed" to the appropriate gauge. It sounds like the Honda fix did the same to the temp gauge. It's the same reading, just an slow average of it. Honda may not call it a voltage limiter.

 

[LarryM]

Todays temp gauges go through a voltage limiter. Just like a gas gauge does. No one want to see the splashed readings of a tank half full. If a gas gauge did not go through one, we would see a gas gauge drop to empty during take off and over full during braking. So a reading is taken every so many seconds and that reading is "pulsed" to the appropriate gauge. It sounds like the Honda fix did the same to the temp gauge. It's the same reading, just an slow average of it. Honda may not call it a voltage limiter.

Greg, what you are referring to is a "weighted gauge". All analog gauges, even ones that respond fairly quickly, have a certain amount of this damping built into them, even accurate linear gauges. Heavily weighted gauges, such as fuel gauge, are sometimes referring to as averaging gauges. If it wasn't weighted, the needle would bounce all over the place. Weighting simply makes it easier to read the gauge.

This is not the same as a non linear gauge. When you see the needles just sitting there and not moving, this is not due to the damping. It is just because the sensor is in its non linear range.

 

[LarryM]

Larry, even my 2004 Montana's temp gauge (which normally sits just below the 1/2 way mark at operating temp), will creep up when I'm pulling my trailer up hill on a hot day. I'm telling you, the needle on the temp gauge on the Wing has NEVER (did I say NEVER?) moved above the "just below 1/2 way mark" ever on my Wing in FIVE years of riding. I have ridden the Wing in some extreme heat, low speed riding, parade riding etc, and its never moved. I don't define that as normal..... but I do define it as unnerving!:? C'mon.... the damn gauge has to move once in a while!!!!! (or is it only at meltdown.... no warning... too late at that point...)

Wingdreamer, I realize you don't know me from Adam. I can only ask you to consider what I am saying here. I know the Internet is full of people who think they know what they are talking about, but this is my professional field. I worked for Electra-Sound here in Cleveland a number of years ago, which is, (or at least was), a major reman center for Ford and Delco Electronics. We repaired and calibrated instrument clusters, engine computers, body control modules, and audio for these manufacturers. I tested, repaired, and calibrated those gauges for GM.

I assure you that your Montana has a non linear gauge. What you are probably noticing is a difference in the width of the non linear region of the sensor. It also could be that your Montana's coolant temperature swings more than the Goldwing. Without seeing the sensor specs, there is no way to know this.

Every manufacturer has a different idea of how wide this non linear range should be, and it even changes from model to model within the same mfr's vehicle lineup. There is no set industry standard for this calibration. It is an engineering decision.

Engine temperatures swing quite a bit during normal use. And there is a range of temperatures that are within normal operating range. Manufacturers make this range non linear on the gauge. This is done to remove the anxiety that a fluctuating temp gauge would cause. It is not done to deceive the driver.

When the engine is operating within its normal range, the driver does not need to know exactly what the temperature is. All he needs to know is that everything is ok, and a non linear gauge accurately gives this information. If your Wing's coolant temperature gets out of that normal range, I assure you, the temp gauge on your bike is going to let you know, well in advance of an overheating condition.

If you haven't seen it, here is a chart I created a number of years ago that shows the sensor calibration and the non linear portion of the gauge. This is taken from actual Honda calibration data, not from a 3rd party source. The temp numbers at the various critical points will give you a good idea of what your gauge is telling you. If you look at it closely, you will see that there is only about a 30 degree non linear range between fully warmed up, and when the needle begins to rise above midpoint.

This should not be unsettling. If your needle does not move, that is a good thing. It means everything is working just fine.

 

[jasnmar]

Thanks for the post Larry. That really helps to explain things. I'd never thought of it as a "pointer angle" problem, but doing so changes the way I think about it completely.

Also interesting the slope of the "pre" and "post" normal operating temperature region isn't the same. While saying that it is non-linear certainly accounts for that, it wasn't what I expected .

Thanks!

 

[LarryM]

Jason, whenever you hear or read about something being linear, it means that if a comparison between two items is graphed, the graph would show a straight line. You could say that the relationship is proportional.

Something that is non linear would show some kind of curvature or deviation from a straight line.

Most times non linearities are not intentional, and are just unavoidable. In the case of a non linear gauge, this characteristic is intentionally built into the design.

 

[jasnmar]

Yea, I get the difference. The graph you show can be broken into 3 linear regions. (I'm making up these regions) Region 1 (low temp), Region 2 (operating temp), and Region 3 (high temp). (OK, technically the "heels" where it transitions from one Region to another would be additional non-linear regions, but pretending that these are "hard" transitions simplifies for discussion rather than the curves that actually exist).

From the previous discussion I assumed that the "slope" of region 1 and 3 would be the same. It isn't. That surprised me. It does, however, show that the slope of Region 1 is steeper than the slope of Region 3, as information on "low temperature" doesn't need to be communicated as clearly as information on "high temperatures" (at least from my perspective). Thinking about it, it is perfectly logical, just surprising

 

[LarryM]

If you compare the upper and lower portions, you will see that there is a wider temperature range in the upper section than the lower section. The difference in the slopes only shows this differential.

I don't want to represent this graph as being more than what it is. It does not have dozens of sample points at the different temperatures. That makes the accuracy of the lines in between data points less than perfect. They are necessary assumptions. The lines might be skewed from actual temps due to the lack of detail. This is unavoidable because it is all the data that is available from Honda. You can't do a detailed analysis with this graph. It is only useful to get a general idea of how the gauge works.

If I were to do this as an Excel graph instead of a manually drawn graph, the statistical trending calculations that Excel performs will probably draw the slopes along a slightly different path. But the idea is the same.

I will have to sit down with Excel to see what it comes up with. Good point you bring up.

 

[2Wheeler]

I am not an expert by any stretch, but I noticed this about a month ago. My gauge stays one notch below the halfway point except when I rode through Cades Cove where everybody crawls along. It then climbed about 2 marks. After I got back on the road it straightened right back out. I think it's because our fans blow toward the front rather than the back. When we ride at low speeds for extended periods, the fans can't move the air and hold the air still, more or less because the velocities are near equal. At least that's one opinion I have heard or read somewhere, probably on this website.

2W

 

[RonnieCole]

Think about the fuel gauge too.

I go much further on the first half of the tank than I do the second half.

I have seen the fuel gauge in an International wrecker with the half mark in a different place other than the middle, where you expect it.

Actually, it probably represents true half full/half empty.

Food for thought.

Ronnie

 

[Wingdreamer]

Think about the fuel gauge too.

I go much further on the first half of the tank than I do the second half.

I have seen the fuel gauge in an International wrecker with the half mark in a different place other than the middle, where you expect it.

Actually, it probably represents true half full/half empty.

Food for thought.

Ronnie

Ok. the fuel gauge has me thinking.... Imagine a fuel gauge that shows full constantly, then when your tank gets down to almost empty, the gauge abruptly, with little warning, drops down to the almost empty point as well. Now, you're scrambling to find a gas station before you run out....... hmmmm... not really that unlike the temp gauge on the Wing. Wont know how hot you are actually running till its a little late....

 

[GoldWingrGreg]

Greg, what you are referring to is a "weighted gauge". All analog gauges, even ones that respond fairly quickly, have a certain amount of this damping built into them, even accurate linear gauges. Heavily weighted gauges, such as fuel gauge, are sometimes referring to as averaging gauges. If it wasn't weighted, the needle would bounce all over the place. Weighting simply makes it easier to read the gauge.

This is not the same as a non linear gauge. When you see the needles just sitting there and not moving, this is not due to the damping. It is just because the sensor is in its non linear range.

You may be correct .. my knowledge comes from the 70's. I take it voltage limiters are not used anymore? And something similar is all part of the gauge itself?

 

[LarryM]

Greg, a voltage limiter, as it applies to gauges, are almost always used to clamp the meter needle when it pegs at its limit to prevent burning out the coil in the meter's movement. But something tells me that is not what you are referring to.

This term might just be a slang which is unique to your field. I am making an assumption that what you call a voltage limiter might actually be an averaging type weighted gauge like what I described previously.

Slang sometimes makes it tough to communicate across different disciplines. I have even encountered it just moving between different fields in electronics.

 

[LarryM]

Wingdreamer, please understand that I am not trying to badger you here. I am only trying to help you understand why meters are designed the way they are so that you can make the best use of them. Please take 5 minutes to digest what I am going to type here.

First of all, for those that won't read this entire post, I would like to post a challenge. I challenge anyone to try and tell me that they know something useful about the engine's operating condition when the coolant temperature is at 190, 200, and 210 degrees, and tell me why. Yes, this is a trick question. So think before answering.

You are 100% correct in your fuel gauge analogy. That gauge would be far less useful if they made it non linear like the temp gauge. But consider a couple of things. I am going to use this analogy in my explanation here.

All gauges, from a simple fuel gauge, to a highly sensitive ammeter, are built with special characteristics to make it easier for the user to obtain the information they need to know. Designers do this by filtering out useless information, leaving only the needed information.

Most gauges, including a fuel gauge give the most useful information when they are as linear as possible. This is because every stage of fuel remaining in the tank, from full, to 3/4, to empty, are all points that are important to the driver. Knowing at any time how much fuel is in the tank allows us to plan our fuel stops.

A temp gauge for street vehicles does not have that requirement. We are given gauges to supply three basic pieces of information. Is the engine warming up quickly enough? Is my engine running within normal operating temperatures? And is the engine running hotter than it should?

Because of all the variables we encounter on the roads, the actual temperatures of the engine whenever the engine temps are within design specs represents useless information. Those infinite variables make it virtually impossible for even the most experienced engine expert to know if a given temperature within the engine's normal operating range is correct for the situation they are in. Many enthusiasts like to believe that they are able to discern this information, but they aren't. They are just kidding themselves.

For a gadget freak, like me, and probably you, it's kinda cool to see what happens in various conditions. But from the standpoint of driving and the information we need to know, it is for the most part useless information.

When non linear gauges were first designed, the idea was driven by manufacturers trying to reduce nuisance warranty claims. Drivers were frequently subjected to extreme anxiety watching the needle of the temp gauge constantly rising and falling. Everyone thought their engines were overheating, when in fact, the fluctuations were perfectly normal.

Nuisance warranty claims are very expensive to manufacturers, and you pay for them in the price of the vehicle. Reducing them keeps the cost of the vehicle down. By creating a non linear gauge, the manufacturer's essentially filtered out the useless information that was causing the anxiety, leaving only the information the driver needed to know.

If you have any doubt as to the severity of the anxiety problems, you only have to read overheating threads within this website. Even with the non linear gauge, many member here freak out unnecessarily every time that needle moves from midpoint, when if fact the engine is working perfectly normal. Can you imagine how bad it would be if this meter were linear?

The non linear range of your temp gauge represents the engine's normal operating range. When that needle sits at midpoint and does not move, it means everything is ok and you can just ride the bike in peace. The only time you need to increase your awareness is when the needle starts to move upwards.

It should be noted here that even if the needle begins to move upwards, the engine is still operating normally. The gauge is just telling you that you need to watch it more frequently in case it continues to rise.

These meters are only designed to give riders adequate information to safely ride the motorcycle. They are not designed for sports enthusiasts. Those types of riders have to go to the aftermarket to address their obsessions with extreme accuracy.

Given the choice, I would prefer to have a linear gauge too. I am confident that I have enough knowledge about how engines work to not freak out every time the needle rises. You might be the same way. I just understand that the vehicles we drive and ride are built for the masses. There are over 200,000 other GL1800 riders out there, and many of them have no idea what goes on inside an engine, and don't really care. And they shouldn't have to know just to ride the darn thing. In the end however, I am content in knowing that the non linear temp gauge the manufacturers use still gives me just as much useful information about the running condition of my engine as a linear gauge would.

I hope you read this, and I hope it helps ease your mind. I hate reading about riders thinking that their instruments are not giving them the information that they need, and constantly worrying about whether their bikes are operating normally. Hopefully I have helped to assure you that your temp gauge really does give you the information that you need to know.