2016 YZ450 Engine Noise

25 replies to this topic
  • mxrider4life847

Posted September 12, 2016 - 06:29 PM


Haha. Well, I found the same thing... When my noise came about, it was after it had boiled over. But I didn't think I lost much coolant. The same trip, I crushed my left radiator.

I never thought to check the water level, but never thought low water would be a symptom of that noise.

So when I pulled the radiator, I noticed the level was low, about 3/4q ( which is about half-ish empty ). I straightened out the rad, re installed and noticed while doing my leak check, the noise was gone... ?

So I took it to a woods race and mx track this weekend... No noise.

  • brad12345

Posted September 15, 2016 - 01:37 PM



  • mxrider4life847

Posted September 15, 2016 - 05:11 PM



Very likely I'm sure. Prob not enough to do any damage, but I plan on bringing my borescope home this weekend and doing some looking around.

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  • JewBilly

Posted September 16, 2016 - 04:41 PM


I did a leak down check on my bike today at top dead center 100 psi, the valves were ok however I was getting a little of air past the rings. Do you guys think this is normal or not enough to be concerned about?


  • grayracer513

Posted September 16, 2016 - 08:29 PM


Rings have gaps at the ends.  They'll always leak,  What was the percentage leaked?

  • JewBilly

Posted September 24, 2016 - 04:28 AM


Had a bad regulator on the first test couldn't figure percentage lost. With the new regulator I'm at 3% to 5% loss witch is good. I've got it all back together and switch the coolant to engine ice so see what it does next time I take it out.

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