Coolant - Just need some straight up answers

[mediumdaddy]

I've freakin googled this to death. everybody says something different. What kind of coolant/antifreeze do i need for my 99 yz400f? The stuff thats in there is green thats all i know. Will regular old autozone green coolant work? do i mix  it 50/50 with water or not? TALK TO ME LIKE IM AN IDIOT, AND TELL ME EXACTLY WHAT TO DO LOL. I wanna flush the coolant before summer hits. Thank you!

[SteveThe Snakes]

I use five year orange stuff. If you ride like a normal person a 50/50 mixture should be good.

 

I don't ride like a normal person so the more anti freeze you put in the ratio the less chance for boil over. I run it straight and have no boil over. The draw back they say is the more anti freeze in the ratio the hotter it runs. If it does boil over real bad and doesn't have enough coolant it can warp the head.

[grayracer513]

Any reasonably good automotive coolant will work.  There are two principal types, Ethylene Glycol based (traditional green stuff), and Propylene Glycol (other colors).  Either will work fine, although PG is slightly preferable.  There is a third kind that you should never use under any circumstance other than temporarily in a dire emergency: "Dex-Cool". 

 

On mixing, some coolants are sold as "ready to use", and should not be diluted before using.  Those sold as straight coolants should be mixed at 50/50 with distilled water.  Water alone has the best cooling capabilities of any coolant used, but boils at only about 220 ℉ under 16 pounds of pressure.  A 50/50 EG/water mix won't boil until 265 ℉, and PG/water closer to 270 ℉ under pressure.

[mediumdaddy]

Thanks for the replys. Gray - How often would you recommend flushing the radiators? It was last done last spring during the rebuild i had done. I'll bet the new top end has around 30 hours max now.

[grayracer513]

It doesn't hurt to change it annually.  There isn't much there, anyway, so it's not likely to be dirty at all.  If you can ground a volt meter to the bike frame and read more than about .5 volts by dipping the other lead in the coolant, you should get rid of it.

[SteveThe Snakes]

Any reasonably good automotive coolant will work.  There are two principal types, Ethylene Glycol based (traditional green stuff), and Propylene Glycol (other colors).  Either will work fine, although PG is slightly preferable.  There is a third kind that you should never use under any circumstance other than temporarily in a dire emergency: "Dex-Cool". 

 

On mixing, some coolants are sold as "ready to use", and should not be diluted before using.  Those sold as straight coolants should be mixed at 50/50 with distilled water.  Water alone has the best cooling capabilities of any coolant used, but boils at only about 220 ℉ under 16 pounds of pressure.  A 50/50 EG/water mix won't boil until 265 ℉, and PG/water closer to 270 ℉ under pressure.

 

Interesting, I've been using straight Dex cool ever since my 89' CR500 days. Use it in both WR450's took the 07' apart very clean looking. Never had a problem usually change it every five years. Might be the new stuff is good ?

 

Some opinions: https://www.google.com/search?q=dex+cool+in+motorcycles&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a&channel=sb

[grayracer513]

Dex Cool is an oxalic acid based coolant. The problem is that it is meant for closed systems only, and tends to oxidize badly in the presence of air. That leads to build ups of sludge.

[72degrees]

We had to drain the coolant from our bikes the other week because we were competing on a race circuit. Just ran tap water but the Motocool went back in as soon as the meeting was over. For speed hill climbs the scrutineering rules don't ban coolant but they insisted we change it as the tyrack was a race circuit. As it's simple on our MX bikes I just did it rather than ask them what they do when road bikes turn up ridden to the circuit to do a track day.

[chevyrulz]

i run "engine ice" brand & it works well...the dirtbike takes so little, i figure why not run the fancy stuff, it's only another $5 or so.   but yes the green stuff is fine, i use the 50/50 already mixed when i buy the green stuff

 

whatever you run, be sure that if it's a type you must mix water with, that you use distilled water

Edited April 24, 2014 by chevyrulz

[Gunner354]

A quote from one of the mags a few months ago. " Just put in Evans and be done with it"

[chevyrulz]

^damn, i thought i was using the fancy stuff,  $50/gallon? no thanks! hahaha

 

I am glad to know about it though

Edited April 24, 2014 by chevyrulz

[Hurricane]

A quote from one of the mags a few months ago. " Just put in Evans and be done with it"

That's what I did... Awesome stuff and it will not overheat.

[grayracer513]

Well, it won't usually boil, but overheating is another matter.

[yteka99]

I've ran engine ice in every bike I've ever had. I could clearly tell the difference in my R1, it ran on the fan a whole lot less. I've been putting it in my cr250 and I'll be putting it in my new yz450f soon. If it works so well in my street bikes I have to imagine it'll do the same for a dirt bike.