black debris / gunk in engine- PIC inside

5 replies to this topic
  • Dan_Man

Posted March 17, 2010 - 04:35 PM


took apart the motor and found black goopy stuff on the bottom of the motor. is this bad? where does it come from?

Posted Image

  • KJ790

Posted March 17, 2010 - 06:47 PM


Have you ever fried a clutch in that bike?

  • Dan_Man

Posted March 17, 2010 - 07:57 PM


no, but its still the original clutch and it has a lot of hours

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  • hydmech

Posted March 17, 2010 - 08:00 PM


Do you use synthetic oil? if your using standard oil you might be cooking it if its getting really hot.

  • Dan_Man

Posted March 17, 2010 - 08:14 PM


always synthetic

  • Padgett

Posted March 18, 2010 - 04:18 AM


That is a common thing. Your always going to have some fine gunk like that on the little lips of the cases. What is it? Fine particles of clutch fiber mostly, broken down oil and so on. What you want to look for in that gunk is shiny silver slivers. The gunk is like a tar pit to trap anything floating around in the cases. Now you may have a small amout of slivers from normal wear, but realy need to look for slightly larger slivers that may be telling you that a problem is in here, check it out.

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