High wear parts in the 426 motor!?!?

2 replies to this topic
  • Pincushion

Posted May 08, 2007 - 06:34 AM


I've got the bike stripped down for painting and figured I'd go through the motor and see how things look. I rebuilt the motor 2 years ago (new oil pump, numerous gears, piston, 450 cam, cam chain....) and figured now would be a good time for an inspection. It's a 2000 model year and I'm aware of the CB key issue, but what else?

I hear a ticking sound coming from the head at idle, but I think its normal valve train noise. Other than that she purrs. What in the head is causing this ticking noise? What are the high wear items in the top end of this motor? I dont feel the cases need to be split, so no need to mention anything below the jug.


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  • Markopolo400

Posted May 08, 2007 - 12:56 PM


My 400 started making a ticking noise as well in early April.

I replace my entire valve train, piston, and cam chain.

I suspect it was the cam chain making the noise, but It's nice to have a completely fresh engine.

  • Pincushion

Posted May 08, 2007 - 01:55 PM


It certainly could be the chain or that I'm using the 450 cam and the tooth pitch discrepancy maybe causing some extra clatter. I've only got about 25 easy hours on the chain, so I know its not at its limit.

Thanks for the input!

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