06 kx250f knocking... PLEASE HELP!

[allmoto616]

Ok... my P.O.S. four-stroke is making a pretty serious knocking sound. It didn't happen all the sudden, actually got worse and worse in a fairly linear progression. After tearing into the thing and checking the play in the big end+small end of the rod (which we were pretty sure was the problem after hearing the noise), we found it to be well within service limit... :think:

I am looking for any and all advice/help on this. The manual suggests it may be a faulty CDI, so I need to find some way of testing that (anyone in the central ohio area with a 06 kx250f i could plug mine into?)... Also, I am open to all other options as to what the problem may be... What goes wrong on these things? Oil pump? Decompressors? etc... Any past experiences anyone can share would be greatly appreciated... Not to mention any recommended people that I could contact that works on these things so I can pick their brain. Thanks for reading...

 

[_JOE_]

How are the valve clearances?

 

[allmoto616]

Checked them not long before the incident... and they still check out good. Contact patch with the seat is a little high on the valve, but nothing too bad. Thanks anyway.

 

[_JOE_]

Hows the piston skirt clearance?