Evans NPG+

[Perky]

I know this topic has been visited before, NPG/NPG+ Thread but I didn't see very many responses on the subject. Has anyone used NPG+? And what, if any benefits have you seen by switching to a waterless coolant.

I know that running pure water with an additive would give the best heat transfer, but does the higher boiling point of Evans NPG+ offset this? Living in Florida, the temps can get quite high, and the humidity is sometimes unbearable. I know the bike will run hotter with NPG+, but will the coolant reduce the problems in the long run because of the lack of water and the low pressure? I'm trying to way the pros and cons to decide if this is worth the cost.

I appreciate everyone's input on this.

Thanks.

-Steve

[Byrdman]

There are three advantages of the Evans NPG+.

1. Very low system pressure is good for both seals and hoses. Many users run no thermostat!

2. A boiling point near 370°F means better heat transfer. Because there is no boiling the hot spots in the engine actually get in contact with coolant instead of boiling bubbles normally found in normal coolant.

3. There's no water which means there's no corrosion.

Your temp guage will actually read a bit higher running Evans because the heat that was trapped inside your engine is now being more efficiently transferred into your cooling system.

I have probably 25K worth of riding with Evans in the engine. I would definitely do it.

[Perky]

There are three advantages of the Evans NPG+.

1. Very low system pressure is good for both seals and hoses. Many users run no thermostat!

2. A boiling point near 370°F means better heat transfer. Because there is no boiling the hot spots in the engine actually get in contact with coolant instead of boiling bubbles normally found in normal coolant.

3. There's no water which means there's no corrosion.

Your temp guage will actually read a bit higher running Evans because the heat that was trapped inside your engine is now being more efficiently transferred into your cooling system.

I have probably 25K worth of riding with Evans in the engine. I would definitely do it.

Thanks Byrdman. You seem to be the only one who has tried NPG+. I think it is worth it, but I just wanted to hear from someone who has already made the switch. From all the articles, it really does seem to be an improvement over standard coolants.

I still have a couple of questions if you don't mind.

1. What did you use to flush the system with?

2. Any special techniques for flushing and refilling?

3. Did you remove the thermostat or plug any lines?

4. How much NPG+ do I need? I was thinking 2 bottles would be enough.

[Justin]

I have always used Engine Ice, and swear by it ... is Evans a similiar product?

[Perky]

Evans NPG+ is a coolant, and is similar to Engine ICE in that they are both relatively non toxic. Evans NPG+ is different because it does not contain any water, where Engine ICE is a pre-mixed coolant/water combination. Evans NPG+ also allows the entire cooling system to run under very little to no pressure. You can find more information here.

[Justin]

Evans NPG+ is a coolant, and is similar to Engine ICE in that they are both relatively non toxic. Evans NPG+ is different because it does not contain any water, where Engine ICE is a pre-mixed coolant/water combination. Evans NPG+ also allows the entire cooling system to run under very little to no pressure. You can find more information here.

Sounds interesting ... I like the "lifetime coolant" point ... just so I am not mistaken ... do they actually mean lifetime? Like I won't have to change it again

[Moriartii]

Ok I gotta differ with you on this one, how can running without a thermostat be smart in the least bit? That goes against all that is good and proper? Yes I am stirring the shit a little but all seriousness I cant see how that could be good?

Kinley

[Perky]

Ok I gotta differ with you on this one, how can running without a thermostat be smart in the least bit? That goes against all that is good and proper? Yes I am stirring the shit a little but all seriousness I cant see how that could be good?

Kinley

From what I understand, by removing the thermostat, you are allowing a more free flowing system. Since the coolant does not boil over, the engine is immersed in the liquid constantly. If you leave the thermostat in, then you will restrict the flow until the temperature is high enough. Someone correct me if I am wrong.

-Steve

[The Krypt Keeper]

Ok I gotta differ with you on this one, how can running without a thermostat be smart in the least bit? That goes against all that is good and proper? Yes I am stirring the shit a little but all seriousness I cant see how that could be good?

Kinley

From what I understand, by removing the thermostat, you are allowing a more free flowing system. Since the coolant does not boil over, the engine is immersed in the liquid constantly. If you leave the thermostat in, then you will restrict the flow until the temperature is high enough. Someone correct me if I am wrong.

-Steve

You are correct, this isn't like a car where you need a thermostat to produce heat in the winter. The bike will always be cycleing the coolant throughout the engine and not only when the thermostat gets to the desired temp to open up and allow flow...

I don't know what effects it has on a bike, but I know I am anal and wait till my bike is warmed up and the thermo working before pulling off... I know then my bike it up to temp to rape some asphalt...

[ironmike]

It may not be that significant in our 'Birds, but I once had an GM engineer explain in numbing detail how a properly calibrated thermostat was critical to maintaing an optimal operating temp for an engine in its intended application (in this case it was a 24 hrs endurance - at WOT - testing protocol on a closed track).

But his point was that ironically it was more important to daily street driving. The issue was that the amount of time the coolant spent in the radiator (where the heat transfer to ambient air occurs) was critical - too little time spent diminishes the efficiency of the cooling system, degrades the effectiveness of pre-programmed ECM maps, and introduces other heat related issues otherwise avoided.

Food for thought...

:icon_think:

[Byrdman]

Thanks Byrdman. You seem to be the only one who has tried NPG+. I think it is worth it, but I just wanted to hear from someone who has already made the switch. From all the articles, it really does seem to be an improvement over standard coolants.

I still have a couple of questions if you don't mind.

1. What did you use to flush the system with?

2. Any special techniques for flushing and refilling?

3. Did you remove the thermostat or plug any lines?

4. How much NPG+ do I need? I was thinking 2 bottles would be enough.

1. I flushed mine with Sierra coolant I believe. Whatever you use to flush the system, it has to be non-aqueous.

2. Pull the drain plug on the water pump and use compressed air to "burp" the system.

3. In all three bikes where I run Evans, I left the thermostat in place. I can live with two pounds of system pressure.

4. I think that two, one gallon jugs will be plenty.

[Byrdman]

It may not be that significant in our 'Birds, but I once had an GM engineer explain in numbing detail how a properly calibrated thermostat was critical to maintaing an optimal operating temp for an engine in its intended application (in this case it was a 24 hrs endurance - at WOT - testing protocol on a closed track).

But his point was that ironically it was more important to daily street driving. The issue was that the amount of time the coolant spent in the radiator (where the heat transfer to ambient air occurs) was critical - too little time spent diminishes the efficiency of the cooling system, degrades the effectiveness of pre-programmed ECM maps, and introduces other heat related issues otherwise avoided.

Food for thought...

:icon_think:

You are correct Mike, for every engine there is an optimum engine operating temperature that creates the cleanest/most efficient burn process.

This is why I left the thermostat installed.

[Pete in PA]

All you guys living where it gets colder then 80F (most of us) do yourself a favor, leave your thermostat in.

[Perky]

Just a quick update.

After researching all of the different coolant solutions and hashing it out with some engineers, I finally settled on a coolant.

I ended up with Preston 50/50 mix.

After talking with the cooling specialists at Peterbilt, they convinced me that what is recommended in the manual from Honda is the most appropriate fluid. :icon_duh:

It was quite fun going over all of the cooling properties of the different mixtures and coolants. I spent about 2 hours on the phone with the engineers hashing it out with them. We looked at the cooling properties of NPG+, Ethylene Glycol, EngineICE, Propylene Glycol, and several others, and their different mixtures with water. I now know more about coolants than I ever wanted to know.

Based on my riding style, and the conditions I ride in, the Ethylene Glycol 50/50 mix was the best choice for me. The 50/50 mix is not right for every condition, but for what I do, this was the right coolant. After changing the coolant, the average temp dropped by about 5 degrees and I haven't had the temp guage get over 220 degrees in traffic.

FYI- the best cooling combination, according to the engineers at Peterbilt, is propylene glycol water mixture around 45% propylene glycol and 55% water. This mixture gives the best thermal transfer.

[EVLXX]

It may not be that significant in our 'Birds, but I once had an GM engineer explain in numbing detail how a properly calibrated thermostat was critical to maintaing an optimal operating temp for an engine in its intended application (in this case it was a 24 hrs endurance - at WOT - testing protocol on a closed track).

But his point was that ironically it was more important to daily street driving. The issue was that the amount of time the coolant spent in the radiator (where the heat transfer to ambient air occurs) was critical - too little time spent diminishes the efficiency of the cooling system, degrades the effectiveness of pre-programmed ECM maps, and introduces other heat related issues otherwise avoided.

Food for thought...

:icon_think:

You are correct Mike, for every engine there is an optimum engine operating temperature that creates the cleanest/most efficient burn process.

This is why I left the thermostat installed.

triple that.

[Byrdman]

FYI- the best cooling combination, according to the engineers at Peterbilt, is propylene glycol water mixture around 45% propylene glycol and 55% water. This mixture gives the best thermal transfer.

Actually, the most thermally efficient mixture is almost 100% water. The problem is that mixture will provide absolutely no corrosion protection and no water pump seal lubrication.

That's why everyone says to run between 25% and 50% coolant.