Topping off coolant...

[john hubbard]

I've noticed that since the weather has gotten warmer (80-90's) that I have to top off the resovoir about every other ride...I have a 02 200 with typical mods and ride fairly aggressively most of the time. It's not that coolant gets real low or anythng like that, but it just seems to drop a cm or 2 after each ride. Is this normal? This is my first watercooled bike. Previous rides were big bore aircooled european rides from the late 70's and early 80's.

 

[jaguar]

Just to be sure, why don't you clean out the radiators with radiator flush (an acid that removes the mineral coating that restricts cooling capacity) and then put in 50/50 antifreeze/distilled water.
You could also play with the jetting and see if you can go a tad richer which would make it run cooler.

 

[89kdx200rdr]

make sure the lines from the resovoir (behind left side panel under rear fender) aren't pinched. also there should be a nut just aft of the plug, loosen and fill till coolant comes out. i always lean my bike left and right just to make sure its full.

 

[jaguar]

My bike will not maintain a full level. Probably due to thermal expansion, the after-ride level is always about halfway between full and the top of the inner ducts.

 

[john hubbard]

Jaguar, I flushed the radiators recently and used the 50/50 antifreeze/distilled h20. I noticed that it really dropped when the bike was running a tad lean one day....As a matter of fact the engine REALLY warm that day. I've since correct the lean condition and I tend believe as you noted that it is due to thermal expansion, but i'll probably richen it just a tad more.

 

[Braahp]

Just leave it dry. Mine has been dry now about 2 years after I got tired of topping it off to no avail. As long as you got it in radiator its fine. A lot of folks just take it off completely. And you guys running hot get rid of the 50/50 mix. Water transfers heat better than coolant does. Maybe try like 80/20 or 90/10. Just keep a little in there to ride in winter months so it won't freeze. Redline "Water Wetter" works pretty good too with just straight water.

 

[android86]

i would def. keep it at or close to 50/50 unless you drain it in the winter. If you leave it 90/10 your radiator and block will most likely crack when it gets
cold.

 

[Braahp]

Of course..........add more if you live or ride in freezing stuff.

 

[Glitch]

I thought that you run anti-freeze in part to prevent corrosion or deposit build up. So, for the summer when its gonna be in the 90's and never below 70, would it be ok to run 90/10, for better heat transfer?

 

[FLBob]

Braahp-Are you sure? I used to think water was better at heat transfer but I've read somewhere that I believed that anti-freeze actually helped the heat transfer-and it wasn't an advertisement.

 

[skipro3]

Nothing transfers heat faster than water. But...when it gets to 212 degrees, air bubbles interfer with the wetting action, as in there is less water to metal contact. So now the bike gets hotter, more air bubbles, less water to metal contact and the cycle begins. Antifreeze (antiboil) prevents that but at a price, namely the ability to transfer heat. One product I use is NPG+ from Evans. It is non-water based and doesn't expand when warmed up like water does, so no spilling coolant past the pressure cap. It can run up to 250 degrees without any problem, first hand experiance.

 

[JasonWho]

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[jaguar]

If not going with the Evans stuff, then I'd recommend trying different ratios of antifreeze and water and see how high a percentage of water you can have before you run into the problem of losing coolant due to excessive boiling.

 

[Houndog]

The antifreeze also has some lubrication properties that help the waterpump...

 

[canyncarvr]

KDX reservoirs lose water all the time. Having it low or even gone after a ride isn't unusual.

Once the coolant is boiling, it's lost most if not all of it's effectiveness. That's why it's under pressure...to raise the boiling point.

I tried running without it altogether. Then the rad level went down. Whatever the amount loss, the res is evidently capable of returning at least some of the overflow to the cooling system.

I put mine back on.

If you ride without one and have no trouble maintaining coolant level....great. There has to be more air getting thru the RH rad ('H' models) with the res out.

Antifreeze does not 'help' heat transfer. Running 90/10 for the purpose of increasing such transfer is counterproductive.

Something that didn't expand when heated would be cool.

Well, doesn't expand as much as water anyway. Physics pretty much requires it to expand some.....

 

[JasonWho]

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[jaguar]

I ran the overflow tube up and over the other side of the fender. The extra height really does help keep it in. Also I kinked the tube with wire where it leaves the reservoir. I did this to restrict its ability to spit out coolant but its only partially kinked.

 

[JasonWho]

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