Coolant leak...Overheating?

Started my YZF 450 04 the other day in my garage and let it run for about 5 minutes. I noticed some green coolant started to leak out one of the pipes that hang out the bottom of the bike. This happened after about 5 minutes of the bike running stationary. Is this because it was starting to overheat and this is the overflow pipe?

I am aware that the 450's can overheat quickly if you let them sit with the engine running. Is this all it was? I tried to look in the manual but couldn't find anything about the pipe that was dripping the coolant out of it.

Why did you let it idle for 5 minutes. I would say it is an overflow, dont hold me to it, I dont know what Pipe your refering to

Its one of the clear pipes that just pokes it head out near the stock black bash plate. After a clean I spray my engine etc with WD 40 and my bike hadn't been started for a couple of weeks, so fired it up and waited for the WD 40 to burn off. It probably was less than 5 min. Probably more like 2 min. As soon as I saw the coolant dripping out I stopped the engine. I'm assuming its the overflow pipe. Will monitor next ride. Just wont let it idle too long next time.

2 or 3 minutes idling without a good breeze across the radiator, it will push coolant out. Follow the hose back up. If it was the radiator overflow, that's what did it.

Letting one idle for a couple of minutes sure will cause it to overheat..These bikes need air flowing! I know at night when I'm racing and sitting at the start gate I can't idle long at all cause it will overheat plus the pipe will turn cherry red. When it first happened to me I thought something was wrong..

Can you put a different radiator cap on that will stay under pressure a little longer. I have this problem on the trail when it gets tight, and I'm around 7k altitude so it boils over a little faster.

I've already put that turkey baster overflow mod on and it works great, but I'd like to try and keep the coolant in the radiators and not the overflow bottle.

Are WR rads larger and fittable?

Can you put a different radiator cap on that will stay under pressure a little longer. I have this problem on the trail when it gets tight, and I'm around 7k altitude so it boils over a little faster.

I've already put that turkey baster overflow mod on and it works great, but I'd like to try and keep the coolant in the radiators and not the overflow bottle.

Are WR rads larger and fittable?

the wr rads are larger and do fit, instead of buying those take a look at the fluidyne rads at fluidynepowersports.com i've seen them as low as $349,try some evans NPG-R also,it has a boiling point of 400'@7 psi!. :)

You can also change the cap, get a high pressure one for a kx65 and it is a 1.8 cap verses the 1.1 that is stock on the bike. I did that to my old 426 and never lost coolant again!

Engine Ice works great!!

Thanks for the heads up guys. :)

the wr rads are larger and do fit, instead of buying those take a look at the fluidyne rads at fluidynepowersports.com i've seen them as low as $349,try some evans NPG-R also,it has a boiling point of 400'@7 psi!. :)

Did you ever find the left side radiator you were looking for?...

Engine Ice works great!!

whats that? is it a type of coolant?

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