Smoking chimney 03 450

1 reply to this topic
  • stev0

Posted August 08, 2012 - 11:58 PM


A mate has a 450 that smokes when cold and smokes a little less when on running temp. He had the compression tested of the cylinder and it came to 4 bar.

Would this just suggest rings or rings and piston?

Bike runs fine and pulls okay, but sometimes has a habbit of stalling if you are not careful with your clutch technique when pulling away.

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  • grayracer513

Posted August 09, 2012 - 07:58 AM


Compression tests on engines with auto decompression are somewhat useless, and have very little meaning. Leak down testing is far more relevant. But if it smokes and uses oil, it can really only be rings and/or valve guide seals.

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