rod bearing gone 07 yz450f

Any one else had a problem like this , 07 yz 450f bought it in may 07 , changed oil every 3 rides , last week seemed louder in crank area than normal .Opened side last night and you can rock the crank and slightly see the rod stay still and there is metel in oil filter . I ride hard but have maintained bike well I thought , I bought yamaha because I thought they were most reliable , now Im wondering , , going to tear it down this weekend and get a closer look but real disappointed right now

man that sucks! I have an 07 as well, and so does my buddy, his Motor always sounds louder than mine does, but I ride mine alot harder than he does..

Be sure to give us a full report on what you find..

i just bought an 08 and so did a friend and mine has alot more engine noise than sounds like a bearing too.oh well,im just going to ride it and do the regular maintenance stuff like i always do and it should be fine.

Has the clutch cover ever been off? Not the small cover, the big cover that has the water pump housing.

There is a small nipple on the end of the crankshaft that fits inside a rubber seal pressed into the the inside of the clutch cover. Oil under pressure from the filter cavity is directed to the crankshaft and lubricated the big end of the rod.

If the clutch cover isn't carefully installed the end of the crank can roll the lip of the seal over and no oil (or diminished quantity) will reach the rod bearing causing an eventual failure.

Only the small clutch cover has been off to put a rekluse in a month after I got it in may 07.I will look for that when i tear it down mabee a factory misalighnment, thanks , would be nice to find a cause of the problem instead of just it went out .

tore eng down last night and rod big end side shot but also piston and cyl shot , this sux

Do you have any pics?

no pics but I will try and take some tonight of the cyl , cant see rod bearing on crank but has definate play and source of knocking , piston doesnt have any bad damage and can still turn rings by hand , looks like the plating just come loose on cyl got in everything and made bearing fail on crank rod bearing , cant see bearing ,still intact but rod moves up and down on crank . Bike actuly run great ,cranked it first kick before starting to look for knock with hose and decided it was loud enough to start tearing in to it and find the source

Well eng is at dealer , they are going to try to get warranty on it , keep my fingers crossed .

Sorry, got pics and got them into my email but cant figure out how to post them here , can any one help or let me just email them to some one and post them for me . Thanks

You need to post the pictures on a hosting site, such as Photobucket, then link to them.

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