426 knocking under a load

2 replies to this topic
  • Grasty_21

Posted January 20, 2002 - 03:29 PM


I have a 00 426, yesterday it started making a knocking noise off and on while I ride. You can not hear it at an idle, but if i rev it just over idle and let out the clutch enough to put a load on the motor its pretty loud. I do oil changes every other weekend and I only run unical 110 fuel also that day I put a new chain and sprocket on it. I left the chain a little tight expecting it to stretch, but it didnt. I only rode it for about 30 minutes like that then loosened it when it didnt stretch a bit. Could this have anything to do with the noise? Any help will be greatly appreciated. Thanks

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  • MikeOK

Posted January 20, 2002 - 04:56 PM


do a search on "cb key" I think this will answer your question. It's a relatively good problem to have since it's an easy fix...

  • oldnbold

Posted January 21, 2002 - 05:40 AM


I did a whole top end job on my old 98 400 because it was knocking after about 200 hrs. All parts of the motor were in spec, re-ringed it and rode it and still knocked.

It turned out to be the chain slapping through the nearly worn out top slider on the swingarm. Sounded just like an engine knock. Experienced it when high torque, low rpms i.e exiting tight corners in a tall gear and hard on the gas.

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