KDXRIDER.NET

I have a question about the KDX coolant return tank,Is it really necessary??I realize its there for reliability but I'm setting up my 1990 KDX 200 for Northern California Hare Scrambles and was wondering if any of you folks have removed yours.

I currently race Scrambles with my CR 250 and I never overheat during a race,We really don't have much tight woods racing in this region.

Any Info is appreciated.

YES!
It's there, keep it, fluid will expand when warm (even when not overheating), where will it go if you remove the overflow? Most importantly, once the coolant is gone, you will run with less cooling efficiency, IMHO bad idea.
my .02 cents
wilf

I took mine off. 2004 KDX220. I race eastern Hare Scrambles. I used to overheat almost any time I got caught in a bottleneck during a race. I took the bottle off and replaced the radiator cap with one from a KX500. The cap was marked 1.9 on the top. Remember, the bottle obstructs much of the air flow around that radiator. Since I took it off I've raced about 8 races, even in the summer. Its never overheated again.

I believe the 220 has more overheating / cooling issue than the 200

Cooling in the two bikes (200/220) is not the same...the 220 does indeed have cooling 'issues', the 200 does not. That a general statement referring to 'H' models.

That has no bearing on a 1990 KDX, however.

My question: 'Why?'

As stated, reliability is at question, so why take it off?

Is your res under the rear fender? I don't know when that changed in the 'E' series. Yeah...could go look it up...but I don't wanna.

A 1.9 cap? Yeow! Just 'cuz it fits don't make it right. If you drain all the coolant OUT it will never LEAK..is that a good plan?

Call it 'input'..maybe not 'info'...but, keep it on.

FWIW the coolant return tank provides a means of capturing coolant loss when the coolant system pressure is above that for which the cap is rated. All liquids expand upon heating but most expand VERY little. A 50/50 ethylene glycol / water mixture would expand about 1% for every 40F of temperature increase, so maybe 2-3% expansion? The air gap below the cap probably covers that . . .

They put it there for a reason IMHO. What are the benefits of taking it off?

Ondatrail wrote:They put it there for a reason IMHO. What are the benefits of taking it off?

It's been said:

Remember, the bottle obstructs much of the air flow around that radiator.

canyncarvr wrote:

Ondatrail wrote:They put it there for a reason IMHO. What are the benefits of taking it off?

It's been said:

Remember, the bottle obstructs much of the air flow around that radiator.

missed that . If thats the case why can't you mount it somewhere else? Still don't think It makes that much difference but the closest thing I come to a dessert here is a sandbox

It is ok to remove 95 and up catch bottles.Install 1.6 rad cap. Mix 50%glycol/50%water and WATERWETTER Motor will run 20% cooler.Will be good for all but extreme conditions

When I built my hybrid I used the kdx 200 rads with no expansion bottle.Irace enduro and hnh and never overheat or lose any water.