Author Topic: Best Coolant for ST1100  (Read 11392 times)

Offline kappy5003

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Best Coolant for ST1100
« on: July 20, 2014, 11:42:47 AM »
I did a search for a post on this but after 1/2 hour I gave up.

I'm sure its come up before but I'm cooling system update, hoes etc and about to reconnect so can anyone advise the best coolant for AnaSTasia.

I recall something about low silica or something to that effect.

Thanks  in advance.

Kappy
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Offline alans1100

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Re: Best Coolant for ST1100
« Reply #1 on: July 20, 2014, 01:33:07 PM »
I'm using the Nulon red coolant which I bought from Supacheap. Mine wasn't premixed so I had to buy some de-mineralised water as well.

http://www.supercheapauto.com.au/online-store/products/Nulon-Red-Long-Life-Anti-Freeze-Anti-Boil-Concentrate-2-5-Litre.aspx?pid=106643#Cross
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Offline Bluey

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Re: Best Coolant for ST1100
« Reply #2 on: July 20, 2014, 02:45:14 PM »
I'm also using the Nulon Red - I bought mine pre-mixed (also Super Cheap), but it is the same stuff. I used demineralized water to flush the system before replacing with the Nulon Red.
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Offline Piet

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Re: Best Coolant for ST1100
« Reply #3 on: July 27, 2014, 11:08:18 PM »
Have you considered Evans waterless coolant?
Thats what I am going to use shortly in mine. 
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Offline Wombat

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Re: Best Coolant for ST1100
« Reply #4 on: July 28, 2014, 01:26:06 PM »
If you are ever unsure go Honda as they do spend a lot of money developing engines etc with lube and coolant.  :grin

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Offline ST2UP

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Re: Best Coolant for ST1100
« Reply #5 on: July 28, 2014, 05:31:36 PM »
I'm using the Nulon red coolant which I bought from Supacheap. Mine wasn't premixed so I had to buy some de-mineralised water as well.

http://www.supercheapauto.com.au/online-store/products/Nulon-Red-Long-Life-Anti-Freeze-Anti-Boil-Concentrate-2-5-Litre.aspx?pid=106643#Cross



Same same here.....Saaz too, Abe use's this product as well, but I think its the pretty pink colour that attracts him  :whistle :nahnah
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Offline saaz

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Re: Best Coolant for ST1100
« Reply #6 on: July 28, 2014, 06:03:02 PM »
Nulon red premix meets specs, and you don't have to bother with getting demineralised water.  I also use it in the car so saves having different coolant around the place.
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Offline Bluey

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Re: Best Coolant for ST1100
« Reply #7 on: July 28, 2014, 09:21:26 PM »
I used the demineralized water to flush only, used the premix as it comes. From what I remember, some coolants should not be mixed, so I was conscious of the (possible) need to get the old green stuff out. Did no harm to flush anyway.
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Offline kappy5003

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Re: Best Coolant for ST1100
« Reply #8 on: July 28, 2014, 09:52:03 PM »
I got the Nulon 2.5litre concentrate, I have pure distilled water to mix it.

That'll go in soon.

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Kappy
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Offline Old Steve

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Re: Best Coolant for ST1100
« Reply #9 on: July 29, 2014, 12:57:58 PM »
Those red coolants are probably a technology developed to meet GM's "Dexcool" specification.

Instead of additives which form a hardish layer over the internal surfaces (this can then flake off and cause water pump failures), the GM type coolant uses Organic Acid anti-corrosion technology (OAT).  In an OAT coolant, the organic acid salts stay in suspension until a corrosion site starts (a galvanic site forms) and they are then electrostatically attracted to the site, covering it up until the electrical potential equalises and the anti-corrosion inhibitor then returns to solution.  This is why OAT coolants are usually marketed as extended life coolants, the additive doesn't plate out but stays in solution.

It's best to replace old technology coolants every year or so, but OAT extended life coolants need to be changed only every 5 years.

Over the years I've used Caltex Havoline Extended Life Coolant.

No reason why you should not to mix different types of coolant (old technology and OAT) but that dilutes the level of OAT in the coolant system and lowers the protection and longer life available from the OAT coolant.
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Offline Piet

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Re: Best Coolant for ST1100
« Reply #10 on: August 29, 2014, 09:29:57 PM »
Today I completed the coolant change out.  I have chosen to try Evans waterless coolant, as it lasts the life of the engine, does not degrade and is said to have many advantages.

Advantage # 1.
Water based coolant can develop vapour hot spots when the hottest parts actually boil the water in close and cause a vapour bubble.  At this point the engines heat at the bubble location now increases sharply as water vapour is not a good heat transfer compound.  The vapour is only 4% of the transfer efficiency of water.  This can lead to a number of undesirable situations.  This coolant has no water whatsoever and has a much higher boiling point so none of the complications as described.

Advantage #2.
No water means the coolant continues to conduct heat away from the engine even in extreme conditions.  Evans coolant has a boiling point of 375 F or 190 degrees C.  That is a massive margin of greater performance.

Advantage # 3.
Evans coolant means the system no longer needs to be pressurised.  The only reason water based systems pressurise the system is to raise the boiling point because water boils at 212F or 100C.  If a normal engine operating temp is 82C then, one only has an 18 degree threshold before its boiling it head off.  A 50/50 water/glycol mix raises boiling point to 103C.  A 1 bar pressure cap raises the boiling point to 123C. You can see why they pressurise the system because it increases the headroom.  With Evans coolant you can remove the pressure in the system, (includes all the hoses of course), and have an unbelievable 190C system safety factor.  Obviously hoses will last much longer if one removes the system pressure. 

Advantage # 4.
No water at all in the cooling system means no corrosion issues as water is always the root cause of corrosion. Oxidation or galvanic action or is some cases cavitation all damage water pumps and eat away at the block, head, thermostat housings etc.  The build up of corrosion on surfaces as well as the degradation of water based coolant mixtures over time (and in some cases lime-scale) all contribute to substantial degradation in heat transfer from engine surfaces to the coolant. Evans coolant stops these issues dead in their tracks.

Advantage #5.
This is probably a less important advantage but for what its worth,  As water flows through an engine cooling system it is subjected to many obstacles and constrictions. The resulting turbulence creates rapid changes in pressure forcing small pockets of water to vaporize. This process produces voids in the liquid known as "cavitation bubbles". As the pressure normalizes the bubbles collapse generating forces great enough to punch minute holes in the surrounding metal. Evans coolant reduces these erosion factors considerably.

Advantage #6.
This coolant lasts the life of the engine, unless a hose bursts or a stone punches a hole in the radiator.  Just think that using Evans coolant might be the last time you have to ever change the coolant.  No more stripping off the fairings, no more trying to flush the system, (Ron Major's Flush of the block). No more having to watch out for corrosion on the thermostat housing or other hose connections points.  Gone is the hassle of getting distilled water and 50/50 mixes that just cant match the performance of the Evans coolant.

Advantage #7.
If this coolant is polyethylene glycol based, then it is nowhere near as toxic as standard coolants.  I am not a green activist but less poisons into the environment is not a bad thing so another advantage in its favour.

It all looks very good and I was left with only one negative.  Its very expensive.  However if its as good as they say, then its worth it, because it sounds like its really going to keep the engine in a far better state long term than all the regular coolant changes I can manage.
« Last Edit: September 03, 2014, 03:47:59 PM by Piet »
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Offline Nigel

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Re: Best Coolant for ST1100
« Reply #11 on: August 29, 2014, 09:45:43 PM »
Nicely put Piet, but what is "expensive" and is there any special needs, or process, for the change over of fluids? Thanks Nigel,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, :wht11
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Offline Piet

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Re: Best Coolant for ST1100
« Reply #12 on: August 30, 2014, 09:07:12 AM »
Hi Nigel,

There is need of a flushing solution as well as the the coolant.  Each comes in a 1 US gallon bottle, so 3.78 litre bottles.
The "Prep Fluid" or flush bottle costs A$ 70.00 and the coolant "High Performance NPG" costs A$90.00 from a local Melbourne distributor.  The ST1100 requires one bottle of each.  So it cost me $160.00 in what should be my last coolant change.  (I can't afford to treat my Falcon)

The procedure:
There is the need to flush the system with a purpose built flush solution (Prep Fluid) that mixes any remaining water in the engine into solution and when dropped out leaves the engine devoid of water.  Water is the enemy.   I followed the Ron Major instructions on flushing the engine.

I warmed up the ST and made sure the thermostat opened and the prep fluid got around the engine.  When cold I again dropped the cooling system this time rebottling the prep fluid because they say its good for two prep cycles.

Then simply refill the cooling system with the High Performance NPG as you would for any coolant.

I found a simple radiator cap at SuperCeap Auto's.  Its a TRC11 that does not have and pressure rating.  It cost just $8.00.  The only issue I notice, is due to it having ears rather than being round as per the original, getting it on was no issue it slipped past a plastic protector all OK.  But getting it off seems to catch on that same plastic protector.  So in the future when I want to remove the radiator cap I will likely need a philips head to loosen the protector to undo the cap.



This next shot shows the cap interference with the plastic in close.



The manufacturers web site is not 100% up to date it seems as the "Powersports" coolant has been Replaced with the "NPG".    The website address in the US is as follows http://www.evanscooling.com. And the Australian web site with dealer locations is here, http://www.evanscoolants.com.au
I hope this helps.
« Last Edit: December 22, 2014, 08:47:45 PM by Piet »
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Offline ppopeye

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Re: Best Coolant for ST1100
« Reply #13 on: August 30, 2014, 09:25:03 AM »
Nicely put Piet, but what is "expensive" and is there any special needs, or process, for the change over of fluids? Thanks Nigel,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, :wht11

Nigel if you are going to do this let me know and we could have a worsh day and do the two bikes( or more if anyone wishes to)


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Offline Nigel

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Re: Best Coolant for ST1100
« Reply #14 on: August 30, 2014, 09:25:44 AM »
Nice write up again Thanks. Rad cap at No pressure, not sure what the answer to that is. What would happen using standard cap? would it do harm? Keep us posted Thanks Nigel......................  :wht11
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Offline Nigel

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Re: Best Coolant for ST1100
« Reply #15 on: August 30, 2014, 09:30:05 AM »

Nigel if you are going to do this let me know and we could have a worsh day and do the two bikes( or more if anyone wishes to)


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Offline ppopeye

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Re: Best Coolant for ST1100
« Reply #16 on: August 30, 2014, 09:43:01 AM »
Sounds good


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Offline Piet

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Re: Best Coolant for ST1100
« Reply #17 on: August 30, 2014, 10:06:43 AM »
Using the standard radiator cap is a no harm situation.  I just like the idea of removing the pressure as this must have a big effect on the life span of hoses.  I would guess that the hose is better able to take operating temp in its stride than pressure.  Old hoses always look swollen and over time tend to burst at some weak spot in the hose.   
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Re: Best Coolant for ST1100
« Reply #18 on: August 30, 2014, 10:55:19 AM »
I'm thinking that there must be a pressurised cap used, as any expansion of the fluid due to heat would cause it to vent, possible causing air to be drawn into the system should the overflow tank become empty
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Offline Piet

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Re: Best Coolant for ST1100
« Reply #19 on: August 30, 2014, 03:53:08 PM »
Would not the following be true?
If the overflow tank is empty then air would be sucked back anyway, pressurised or unpressurised.
If a pressure cap did not allow suction back into the radiator on cooling then there would be no point in even having an overflow tank.  Its purpose is to keep the system full and the overflow tank is the extra capacity to allow for expansion and contraction.  The ONLY reason they pressurise is to raise the water boiling point to 123C increasing the headroom to cool the engine before it starts to boil and have all the vapour issues.  If it cannot boil till 190C, there is no longer a reason to pressurise.  With fluid that effectively does not boil in normal operation, even on extremely hot days then the expansion tank will continue to work at normal air pressures.  There is no need to add 1 bar of extra pressure to the system.  You can, and it will work fine, but it will also work fine at normal pressure and extend the life of all the hoses.



« Last Edit: December 22, 2014, 07:31:26 PM by Piet »
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Offline Old Steve

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Re: Best Coolant for ST1100
« Reply #20 on: September 01, 2014, 09:06:30 AM »
With only a brief scan of the Evans Waterless Coolant site, I see it has a high BP, low freezing point, and is non-toxic.  On just a quick research I would assume that it's based on polyethylene glycol which is used in food stuff coolant systems (monoethylene Glycol is very poisonous, it has a T50 - half fatal dose - of 300 mL).

However glycol has two disadvantages as a straight coolant.  It is corrosive so needs the inclusion of specific anti-corrosion treatment.  And it has a lower heat transfer rate than water, so will carry less heat away from the engine.

I was amased at what I took to be pseudoscience on the web site, "water contains oxygen so contributes to corrosion" duh?  H2O, yes it contains molecular oxygen, but so does glycol C2H6O2.  What causes corrosion in water is dissolved oxygen and that usually comes from water/air contact, and boiling reduces the level of dissolved oxygen in water - so if you're worried about oxygen in water boil your water before you make your 50/50 coolant mix (though the coolant will have anti-corrosion additives to cancel the corrosive effect of the dissolved oxygen anyway.

I've had extensive experience with cavitation as I have done a lot of work with lubricants and coolants, I once gave a seminar in Asia with a Mecedes Benz representative to the users of MB engines who were using plain water as a coolant (because there's no need for an anti-freeze component, right?) and these engines were experiencing cavitation.  This was the only experience of cavitation that this MB expert had ever seen.  What these users were missing was the additive package which was being left out by not using coolant, and plain water is more susceptible to cavitation than a water/glycol mix.

Personally, I wouldn't use the Evans Waterless Coolant.
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Offline Piet

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Re: Best Coolant for ST1100
« Reply #21 on: September 01, 2014, 05:02:10 PM »
Old Steve,  My friend you are most welcome to choose what you run in your STeed. Thats what this forum is for.  It helps us all to compare and make informed choices. 

Rest assured I have NO affiliation with Evans in anyway whatsoever.  I am not a chemical whizz kid either.  I was quite upfront that perhaps I was sucked in by the sales blurb.  That being said I would like to address some of the comments you have shared. I suspect that Evans coolant is a Polyethylene Glycol H-(O-CH2-CH2)n-OH based product but the blurb does strongly indicate that its not just Polyethylene Glycol.  It states, "Evans Waterless Coolants are patented synthetic formulation blended with a non-aqueous proprietary inhibitor package"   So it seems to me you might have to add a bunch of other stuff as well.  I have not even a guess what the chemical formula might then look like.

The C2H6O2 you reference is NOT Polyethylene Glycol.  Rather C2H6O2 is either ethylene glycol or possibly ethyl hydroperoxide.  So the comments about it being corrosive my be spot on for this formula (hydro peroxide sure sounds nasty stuff) but its not the product under discussion.  I don't think the comments about the science apply in this instance. The fact that Evans coolant is non corrosive would lend some weight to this as well.

Regarding the thermal transfer efficiency.  If we are right that Evans coolant is Polyethylene Glycol based, then it would be true that it is not as efficient as pure water.  A test would show that the solution might be approximately 5C hotter than water given the same volumes of coolant and with exactly the same heat applied.

Now lets put it in an engine.  The thermostat only opens at its set point, so the engine is designed to run at the thermostat temperature.  This would mean the thermostat will open a fraction earlier and then it will control the flow through the radiator in exactly the same way as it does with water.  It should run optimally as designed, perhaps with a slightly higher flow rate through the engine but the cooling system is designed to provide sufficient cooling capacity with its radiator and fan even on the hottest days.  If a standard engine is approaching 123C then vapour issues are very real and I have read stats that as much as 60% of combustion engine failures are due to cooling system failures.  I for one, would value very highly the extra headroom of a coolant that boils at 190C keeping vapour issues to the absolute minimum.

Its been known (rare cases) that a cooling system that was very hot, imagine 120C and someone suddenly removed the cap.  The cap blows off and the engine immediately boils because its 20 degrees over boiling point.  The boiling is very aggressive and the vapour bubbles are thick and fast.  Now the hottest parts of the engine are in contact with vapour and have a 4% efficiency thermal transfer as compared to water.  Engines can be ruined in this scenario.  I lost a head on my S type Jag when a hose burst on me while I was living in Dubai.  You should have heard the bubbling.  If it had Evans coolant there would have been no boiling and no damage (unless I kept driving until the water pump emptied the coolant. )

Cavitation ... As I said earlier, "A less important advantage, but for what its worth" I wanted to share the benefit.
« Last Edit: September 01, 2014, 09:22:45 PM by Piet »
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Offline Old Steve

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Re: Best Coolant for ST1100
« Reply #22 on: September 02, 2014, 09:51:01 AM »
Piet, you're quite right, PEG is H-(O-CH2-CH2)n-OH - I just thought it would be easier for the non-chemists amongst us to understand if I used the simplest formula.  In the case where n = 1, then the formula becomes C2H6O2, monoethylene glycol, when n = 3 the formula becomes:
HO-CH2-CH2-O-CH2-CH2-O-CH2-CH2-OH.  PEG is usually described commercially by it's molecular weight, so you'd specify a long chain PEG as PEG 1000 or higher.  In a coolant you'd only be looking at using PEG in the molecular weight range of 200 to 400 or so, maybe two to 5 or 6 ethylene glycol units in the PEG.

And uninhibited glycols are corrosive, that's one major reason why an inhibitor package is included in the coolant.

As for the actual words Evans use, "patented synthetic formulation blended with a non-aqueous proprietary inhibitor package".  All glycols, mono and poly, are synthetic, they're manufactured.  All coolants have to include an inhibitor package, this is usually based on borates or nitrates but more recently based on organic acid technology (OAT).  Any specific inhibitor package can be varied minutely so that it is a distinct formulation and therefore patentable.  Part of my job was to write phrases like that, so I recognise them for what they're worth.

I did some work during the development of Texaco/Caltex Havoline Extended Life Coolant based on OAT and on the water based inhibitor product.  I toured China for two weeks and travelled through Africa and Asia giving seminars on the product, and helped Mercedes Benz with a cavitation problem they had in Hong Kong/China.  I know a little bit about coolants - or more specifically coolants/corrosion inhibitors/anti-freeze.

Sure a water/glycol mix coolant will boil if someone takes the cap off while the coolant is hot and a glycol based coolant might only spray a little - but I'd put that down as water /glycol coolants supporting Darwinian selection, elimination of the less desirable genetic material.  I just don't see any benefits of using a straight inhibited glycol based coolant.  But that's just my opinion, but it's based on a lot of experience.
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Offline Piet

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Non pressurized radiator- don't go there.
« Reply #23 on: March 19, 2015, 01:13:43 PM »
Non pressurizing radiator cap with Evans Coolant.

Not recommended.  I wanted to, as I felt that hose life would be extended if the hoses did not have the pressure to deal with.  However I kept a close eye on the system and I found that Ron Major's comments were true in this case as well.  Below is an edited version, of Mike's comments that pertain to this. 
:H

"High Coolant Temperature, but Plenty of Coolant in the Overflow Bottle
The problem addressed here is the one where there is no coolant leaking from the system (other than possibly at the small open-end hose attached to the overflow bottle), as detected by drips under the bike or an odor of antifreeze. The cooling fan is also operating when the temperature gauge needle reaches a point about 3/4ths of the gauge maximum.

The radiator cap has a two-way function controlling pressure in the system. There is a relatively large spring holding a plunger with a rubber seal that will serve to release pressure from the system when it reaches the cap pressure rating. This is 16 to 20 psi (1.1 to 1.4 Bar), according to my Haynes manual. By design, the radiator is completely full of coolant at all times. When the engine warms up, this coolant will expand, generating a positive pressure. When this pressure reaches the cap setting, coolant is allowed to pass the cap and flow to the overflow bottle. Note that this occurs every time the engine is warmed up, not just those times when the system is "overheated".

When the engine is turned off and the system cools down, the coolant contracts. This produces a negative pressure in the system. A second check valve in the center of the cap then opens and allows coolant to syphon back into the radiator from the overflow bottle."

I am not sure why exactly but it seems the expansion that takes place would easily pass to the overflow bottle as expected but would not be sucked back into the radiator on cooling down.  As a result "each subsequent cool-down and warm-up cycle will raise the coolant level in the reservoir even more. Eventually there will be insufficient coolant in the radiator and the fan sensor won't be in contact with coolant."  Thats a real problem.

I put my original cap back on and all is sweet.
I have not yet identified where the loss of seal that breaks the suction return from the overflow tank is but suggest caution.
« Last Edit: March 19, 2015, 05:08:53 PM by Piet »
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