Jump to content

99 yz400f crank discoloration

Recommended Posts

Apon removing the jug on 1999 Yz400f found blueing on the crank. It is more wide spread on the clutch Side of the motor. Is this a common occurrence or do I need to be shopping for a replacement

Share this post


Link to post
Share on other sites

The factory uses heat to ease the insertion of the crank pin and alignment.  Every YZF crank is like that.  The bearing could not generate that much heat without 1) turning the big end of the rod black, and 2) failing completely.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×