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Discussion Starter #1
I just recently picked up this bike so I'm pretty new to it and it consistently runs hot with the gauge reading in the middle of the thicker line when the temperature outside is 70+. I've tested the 7 volt regulator and I'm getting 7.3 volts on the green wire and have also replaced the thermostat and that made no change. Any help or ideas would be greatly appreciated.
 

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Can you access a IR temp thermometer?? this will give you an indicator.
When was coolant replaced? when was the radiator last flushed?
The 7v regulator may be fine but the gauge itself isn't all that accurate by design......
I had worrying temp readings but no signs of overheating ...so I added a Daytona Aquaprova gauge on the handlebars 2 years ago and left those variable readings behind-sits at 70-80c now even days of 40 degree Celsius outside temp (110F)
 

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Discussion Starter #3
The coolant was recently change and I let it run for 15 minutes with the cap off the get the air out of the system. I dont have an IR thermometer but I can probably find a friend that has one I can use.
 

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The coolant was recently change and I let it run for 15 minutes with the cap off the get the air out of the system. I dont have an IR thermometer but I can probably find a friend that has one I can use.
The IR thermometer is useful because there is a few possibilities-1. the gauge is reading falsely high and not representing whats happening...or .2. the gauge is accurate and other issues-e.g. partially blocked radiator etc....
Does the gauge fluctuate at all or is it fairly stable?
 

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Discussion Starter #5
The gauge stays in the same spot just below the middle of the thick line unless I stop then it climbs up to about 3/4 of that line. I just check the resistance of the sending unit and got 37.8-40 ohms after a ride while the engine was still hot and the gauge was in the middle of the thick line. From another post I found that ohm reading should be just above 185f or 85c so I'm guessing the gauge it off from the slightly higher voltage.
 

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Seems like normal operating temperature.

You might consider a close exam of the radiator. ie, straighten fins, clean it, check for core blockage......

Otherwise, I wouldn't be too concerned at 185F temperatures.
 

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Discussion Starter #7
Seems like normal operating temperature.

You might consider a close exam of the radiator. ie, straighten fins, clean it, check for core blockage......

Otherwise, I wouldn't be too concerned at 185F temperatures.
There is some slight damage to the fins but nothing I feel is note able. I also changed out the regular and now it reads an 1/8th inch above the beginning of the thick line in 70f weather. So I'm guessing it was just reading high but I wont be able to tell for sure until it gets a bit warmer out.
 

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Discussion Starter #9
Okay so it has warmed up here and my gauge reads in the upper 2/3rds if the thick white line if I leave it idling and I have noticed some discoloration in the first bend of my stock headers. They are turning gold through most of the bend and on the tightest part of the bend, it's turning a little blue. I've flushed the radiator and ran some vinegar to get any deposits out and I checked the water pump all of which seem to be fine.
 

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They are the stock headers...
Since the bike is new to you, how sure are you that the headers have not been replaced with aftermarket single wall stock appearing headers? If infact they are stock, the discolouration would suggest that the inner pipe has rusted through.
 

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Discussion Starter #16
Since the bike is new to you, how sure are you that the headers have not been replaced with aftermarket single wall stock appearing headers? If infact they are stock, the discolouration would suggest that the inner pipe has rusted through.
I have taken the headers off and they looked to be double wall so I'm 99% sure they are stock
 
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