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Discussion Starter #3
Thanks, I just bought my 2004 RC51 two days ago. Got it for 5500. 11,000 miles. Sato exhaust. Nice bike. I'll look into the temps running here in Las Vegas this summer.
 

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Outstanding purchase! read fan upgrade info on this forum. In FL after running back roads and hitting t\lights I reach 220F which will relay your radfans. My RC has reached 230F before process cools to sub220F. Familiarize where you can see fan body through fairing frame crease and make sure they're spinning. I painted yellow marks on mine, like old time timing marks, to make sure they were engaged. Gives me peace of mind!
 

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My system has only reached 224F once, and that was due to a poorly patched hole in the left radiator by the previous owner/bozo.
After I fixed the cooling system, its been working fine.

My engine will get to 221F in stop & go traffic, but will cool down quickly to around 205-208F once moving.
When briskly moving in the city, it will hover around 205-208F.
If I ride in country, I often see sub-200F and I've seen 179F one morning.

The critical temperature is 251F where the temp indicator will start to blink on the panel.
Pull over and cool that engine down immediately when that occurs.

It's interesting how sensitive the cooling system is.
I've been riding along on a country road and pass under a shade tree and immediately see a 1F drop in temp before it returns.
 

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Ask any of the dealers that are sight sponsors or a reputable dealer in you area should have it.
 

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Discussion Starter #10
I just Changed my Coolant to Engine Ice on My 2004 RC51 on Saturday. I drove the bike to work today and it it running about 30 degrees cooler than before. a huge noticable difference.
 

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I just Changed my Coolant to Engine Ice on My 2004 RC51 on Saturday. I drove the bike to work today and it it running about 30 degrees cooler than before. a huge noticeable difference.
This is hard to believe, unless you had insufficient coolant or it had turned to molasses. Are you sure you didn't have a leak somewhere? Some hose connections are known to leak a drop here and there.
Most people say they can hardly feel any difference. Water is the best coolant in terms of sucking heat out of the engine and transferring it to radiators, but it needs to be replaced often. I use a little coolant with purified deionized water and replace it often and never had problems.
Only in below freezing conditions is coolant absolutely necessary so the block or radiators will not crack.
 

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The coolant acts a as surfactant, and allows more water molecules to contact the metal surface of the radiator to transfer heat.

Similar method to washing clothes. The surfactant (soap) breaks down the water's surface tension and allow the water to fit through smaller spaces than water itself could.
The water lifts the soil off the clothes and is held in suspension by the detergent.
 

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Wow, I get to debate with subsailor this time, instead of agreeing with him!
What you say is true, but does it apply? Water passages in a motorcycle engine are not really small enough to be affected, and since normally you have no air or other material between the cooling/heating surfaces (heat transfers from combustion chamber area through aluminum to water jackets, then to coolant, then to radiator passages, to aluminum to air.
I believe negative surface tension slows flow down more than positive surface tension. If you have used mercury balancing tubes you will notice it moves up and down in the thin tubing easily (is it the highest positive surface tension in near atmospheric conditions?).

If you bleed the system right the only other thing that can separate metal surface and water would be vacuum, and as the flow velocity is not that high I can't believe this would really be an issue.

But I think you missed the 30' drop jfm**** is reporting. I can not believe a bike that run 220 is now running 190 with a switch of coolants.

I agree it is good to add some coolant to the water for various reasons. One is Ph balance, the other is to raise the boiling point by a little bit, some of it has to with lubing, etc. But too much coolant actually decreases the ability of the cooling system to suck out heat. I can't find a source, but the heat transfer capacity of water is better than other coolants.



The coolant acts a as surfactant, and allows more water molecules to contact the metal surface of the radiator to transfer heat.

Similar method to washing clothes. The surfactant (soap) breaks down the water's surface tension and allow the water to fit through smaller spaces than water itself could.
The water lifts the soil off the clothes and is held in suspension by the detergent.
 

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Not really a debate as more a discussion based on obtainable information.

What I intended to imply, was the the coolant breaks down water's surface tension and allows better microscopic wetting of the surface area.
Water is the key conductor of heat, it's just the coolant allows water to act more efficiently.
That's why, or course, only enough coolant should be used to augment water, not replace it.

A 30 deg drop in temperature drop measured at exact same conditions would be a dramatic improvement with no other changes in the cooling system.
Now a 30 deg difference between standing at a light vs rolling down the freeway is completely attainable, and I've had those readings before many times, if not better.

Water has the highest latent heat of vaporization of any fluid.
When water changes state from liquid to gaseous form, it transfers a tremendous amount of heat.
Only ammonia comes a distant second.

On nuclear submarines, the primary air conditioning system uses steam as the main heat transfer medium.
Only the backup systems use freon, and they don't have near the same cooling capacity.
 

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Discussion Starter #16
Guys, I know that the 30 degrees difference sounds to good to be true, but the fact that the temperature in Las Vegas yesterday was about the same as the day before, traffic conditions were slightly different. I was able to move through traffic with greater ease and did not have as many stop lights. The antifreeze that the previous owner had in the bike was junk. I place most of the change in temperature due to the Engine Ice coolant being introduced into the bike allowing the bike to run much cooler. anty thoughts are welcome. jfm - 2004 Nicky Hayden Edition RC51, Sato Exhaust, 11000 miles.
 

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Discussion Starter #18
Around town through stop and go traffic, I was running around 205 - 225. After the coolant change, same senario, the temps topped out around 200, usually running around 175 - 180.
 

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very rarely is my bike under 200 if ever while riding more like 210 - 230!! Fans do come on though. Maybe I should try some ice?? I thought about it last year but didn't...
 
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