07' YZ450F Loose Parts in Bottom of motor...

4 replies to this topic
  • jmiller969

Posted September 28, 2010 - 07:21 AM


All -

Looking for some feedback. I have an 07' YZ450f bought her new, cannot tell you how many hours are on here. Oldtimer, change oil every ride, do not over rev, not sure I have ever hit the rev limiter. I have put two new clutches in her, and not had anything else that needed to be done. Changed oil after the weekend and the filter was full of aluminum. The oil was also full of alum. Last summer I had yz250f motor let go as well. One of the bearing retainers deep in the motor came apart and mades its was to the stator and the fire died. I opened the side cases up last night and found a screw and what appears to be one of the cogs off the transmission gears.

My question is this, what is the risk in closing here up and running it? Do I conseed and tear her apart? If I tear it down, should I consider replacing most fo the internal parts? Crank, piston, bearings, transmission, etc???

Any ideas would be appreciated.



  • grayracer513

Posted September 28, 2010 - 07:57 AM


... what is the risk in closing here up and running it?

You're kidding, right? You found a bearing retainer screw and a broken tooth lying in the engine and you would consider running it?

Uh, no.

The fact that there was aluminum in your oil filter means there is aluminum in your oil tank (forward section of the crankcase assembly) also. The whole thing need to be dismantled and reconditioned as necessary. It will only get worse otherwise.

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  • brentn

Posted September 28, 2010 - 09:42 AM


Even if you change the filter, I wouldn't be surprised if there are metal shavings/chunks clogging the oil tunnel that leads to the filter, in which you will starve the head of oil... Pretty sure that the oil goes to the filter, then the head, then back to the tank yes?

Listen to grey!!

  • masterraptor

Posted September 28, 2010 - 12:05 PM


Way less money to tear it down now. May get away with gasket set, a bearing and a gear only.

  • jmiller969

Posted September 29, 2010 - 01:19 PM



She is being torn down.

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