Leaky rad test

I took my bike out for the first ride today and theres still snow on the ground. Theres this nasty hill that I have to go up and its fairly steep and long so I hit it about 3rd tapped. I have a trail tech temp meter on my bike that monitors water temperature and before I went up the hill it read about 55C. Once I got to the top of the hill (thankfully) I noticed my temp was already at 72C. I haven't ridden with a temp meter before, so maybe this is normal.

But when I got off my bike to just take a look at it I noticed some water drip on to my exhaust and bubble up. Seems like its coming right from the rad. Not the water pump weep hole or the over flow.

So to the point, does plugging off your rad fittings and blowing into the rad with your mouth a good test to see if its leaking? Or is there another way?
 
Your wind bag is not enough pressure unless you can blow up a tire as well. (If you can do that, there is a side show in your future at the circus).
You will need to cap of the radiators, leaving the lid on and using one pipe open for a female air fitting. Fill with water, add water coloring, and pump in about 20 PSI first and increase by 10, until you see where it is leaking. Don't go over 65PSI on most radiators.

40PSI is 2.75 bar. That should be all your cap can handle.
 
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For me I would be stopping about where Palmer is starting. My memory of one of the most often read manuals in my collection had my two stroke cr's testing at 16-20 lbs. radiator caps for them and the current crfs are commonly marked 1.1, meaning 1.1 atmoshperes which is about 16-17 lbs if you do the math, again according to my memory. if yours is under 13 you may be getting some blowby and maybe that is what the leak is from. about any auto parts store can test it and sell you a new one.

we got one of Floyd's barflys to see if she could blow up a water bottle one time.
 
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Your wind bag is not enough pressure unless you can blow up a tire as well. (If you can do that, there is a side show in your future at the circus).
You will need to cap of the radiators, leaving the lid on and using one pipe open for a female air fitting. Fill with water, add water coloring, and pump in about 20 PSI first and increase by 10, until you see where it is leaking. Don't go over 65PSI on most radiators.

40PSI is 2.75 bar. That should be all your cap can handle.
For me I would be stopping about where Palmer is starting. My memory of one of the most often read manuals in my collection had my two stroke cr's testing at 16-20 lbs. radiator caps for them and the current crfs are commonly marked 1.1, meaning 1.1 atmoshperes which is about 16-17 lbs if you do the math, again according to my memory. if yours is under 13 you may be getting some blowby and maybe that is what the leak is from. about any auto parts store can test it and sell you a new one.

we got one of Floyd's barflys to see if she could blow up a water bottle one time.
Yeah I was pretty sure that under load the system was only like 15-20psi max. My friend has a test that is basically just a rad cap with a fitting on it so you can hook it up to a compressor and ive used it on sleds before but not dirtbikes.
 
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sounds like it would work for you. service stations used to test caps and entire systems and if you have someone like that handy it would probably work too. you just have to be fast at spraying soapy water. do it cold and you can just start the bike up and start spraying and usually find a leak. but find it!! one way or the other.
 
sounds like it would work for you. service stations used to test caps and entire systems and if you have someone like that handy it would probably work too. you just have to be fast at spraying soapy water. do it cold and you can just start the bike up and start spraying and usually find a leak. but find it!! one way or the other.
Yeah it has to be fixed. I currently have the leaky rad off the bike.
 
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