Cooling

Rumors being what they are..........

I heard an interesting one the other day. That starting in 08, KTM's will be delivered with Evans NPG-R coolant in their radiators. That is what's in the TyDavis Waterless coolant bottles you may have seen on the shelves of your local bike shop. When I get a for sure on this I'll post again.

Thanks for all the great posts,

I have to admit that I have been vascillating on whether or not I'm going to remove the Evans from my system and utilize the brand new bottle of Engine Ice that's been sitting on my garage shelf for the last year.

I have run enging ice in the past, and in my observations it boils over sooner than just regular ol ethylene glycol. Which, by the way makes sense given that propylene glycol reduces heat transfer of water by 20-25%. That would mean, in a given situation a water propylene glycol mix would boil sooner as the actual coolant temp would rise above the boil over pressure restrained point more readily due to it's reduced heat transfer charachteristics.


However, there are certain charachteristics of the NPG-R coolant that I would like to point out and get all of your opinions on.

The main claim here is that there are hot spots in the motor, especially in the cylinder head area, where, as claimed by Evans, a regular coolant is actually film boiling b/c of the high temps in these area's. This means that the water in a regular coolant is turning into a gaseous state, and then condenses as it cools. And, given that the regular coolant is film boiling, it cannot extract the heat because of this vapor barrier, and thus, the temps in these area's will continue to rise and the area of film boiling will continue to increase in size, which increases the area's temps further (to a point of course). Also, as the coolant vapor leaves the area of film boiling, it is in the form of bubbles, which also means that any other area's that the coolant is trying to pull heat out of before reaching the radiator and condensing, will thusly be diminished b/c of said bubbles.

So, Evans claim is that their coolant (which boils at 400 degrees) is far more resilient to film boiling in the cylinder head area. Which if memory serves, can reach temps of 450 degree's. Thus, their coolant stays in contact with the metal surfaces of the motor and is able to extract more heat.

I called Evans the other day and posed the following question to the Tech: When I was riding up in Washington this summer with a friend of mine, who for all intents and purposes was riding the identical bike as mine with the exception that his bike had the stock coolant, I noticed the following upon returning from a long ride. After our bikes had been sitting for about 20 minutes or so, I went over and put my hand on his bikes radiator and it was still hot to the touch. I then went over to my bike and put my hand on my bikes radiator and it was noticably hotter. I realize that this was somewhat subjective as I did not have a spot radiometer to check actual surface temps, it was noticable.

The Tech's response was as follows: Your radiator felt hotter b/c the as with the other bike, the coolant was thermo syphoning, however, b/c Evans coolant pulls more heat out
than water, your radiator felt hotter because it was pulling more heat out of your motor.

Question for Dale: Your post states that when you switched over to Evans that your engine temps went up, and the coolant temps went down. Do you happen to recall what the temps actually were??

Here are a couple of pages for you to peruse:

http://www.eas.asu.edu/~holbert/eee460/ ... erties.pdf

http://www.evanscooling.com/main1.htm

Let me know what you think.

Thanks Dale!!

Finally!! some real numbers to think about.

Sorry to hear about the spanish spec/raditor size thing. As you said, at least you were able to keep running with the Evans.

The distilled water/water wetter definitely sounds good. But, I will need to run something like DEX cool or someother type anti "FREEZE". As it is definitely coming into the the time of year where it gets a bit chilly in the desert. In fact, when I was up at Kennedy Meadows a couple fo weeks ago it was 20 in the morning when I got up.

Thanks again for the numbers,

LINEAWEAVER said:

nsman said:

I noticed Pascal Picotes Yamaha R-1 sported a additional bottom section radiator,shaped like a "V", at the Parts Canada Superbike series at AMP. Guess we know why!

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Indeed! :lol:
The YEC radiator has near four times the area of stock.

FYI:
The AMA neither allows the YEC oil cooler.

The good news is I am now an "AMA Pro Racing" rules committee member. As such I have an official vote.

Dale

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That's great news!!

While you are there Perhaps you could fabicrate and patent an AMA race director's rectal cranial impaction removal device to avoid future Mid Ohio debacles!! :lol: :lol: :lol:

nsman said:

I think DalEO was refering to last weekends dogshow at mid-ohio .The riders said they would not race on a wet track,the AMA said they would not have too.The track advertized the race rain or shine,the AMA said well maybe we will,the riders said NO.and skipped the heats but eventually said yes and started from the back in the final.It was a great superbike race,except that Spies played it safe .Even local Halifax boy Danny Fahie got a TV interview as he was(now pastence) Roger Lee Haydens team manager....Danny stays wirh Kawasaki for next season but RLH is on a Suzuki....
ANYWAY Daleo was hoping you could help the AMA from repeating their last weekends performance....I think...

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You thought correctly nsman!! Although I am now a charter life member in the AMA, I have my problems with them. In my opinion the AMA should be looking out more for the riders safety in many instances. Remember a few years ago and all the BS with the Air Fences??

And, remember the supercross race I believe that was in Las Vegas when most of the track lighting went out? A lot of the top riders had to boycott that race too, but, the privateers couldn't afford to.

The AMA reminds me of USAC back in the late 70's when they almost killed indy car racing b/c of their rule changes etc... The only thing that saved indy car racing was the formation of CART. Wherein the owners got together made their own organazation and they set the rules. The only place that remained that USAC had anything to do with was indy itself. I could go on for pages about USAC'S screw up's as I was, heavy influence on was, a big fan of indy car racing until Tony George graced us with his BS. Alas...... I digress............

So, for clarification, it makes me happy that Dale is on the rules comittee as he is someone who has made his living dealing with these org's and the entrenched mind set's and self serving players on the rule boards.