top end not getting oil!

[whicked450]

i have a 2005 yfz450 and i have blown the motor up twice due to not getting oil to my wrist pin and bottom of piston. i have heard that there is a oil jet or oil passage that needs to be modified. what do i need to due to stop this problem?

Its called the "oil mod" I dont know anything about it. But the 07s come with it done, go on yfzcentral, alot of guys over there do it.

[YFZ450 11x]

How long between the blowups? Have you checked to see if the screen at the bottom of the oil tank was clogged???

[Ride1Rob]

Originally posted by YFZ450 11x
How long between the blowups? Have you checked to see if the screen at the bottom of the oil tank was clogged???

What he said... When I 1st checked mine a couple of years ago it had grass and aluminum covering it :eek2: This is a much cleaner shot with small aluminum shavings.

http://img49.imageshack.us/img49/2861/img0006rj7.jpg (http://imageshack.us)

http://img131.imageshack.us/img131/6885/img0008ap8.jpg (http://imageshack.us)

http://img55.imageshack.us/img55/830/img0007te8.jpg (http://imageshack.us)

[YFZ450 11x]

wow nice job w/ the pics!!! Yea that stupid thing I was trying to clean mine for a while but yamaha made it so "easy" to get at I ended up cutting it right out. I figure I do an oil change after every race anyway.
If your still having trouble this is a link to my engine builder BCS (http://www.bcsperformance.com/index.html). His name is Jay and he knows a YFZ engine inside and out. He did my oil mod and wr crank and oh yea my port and polish job :D