Aluminum in Engine Oil?

[ajw9173]

Hey everyone. I have an 07 450r. I Drained the oil out of the crank case and found some substantial metal bits in it, as well as in the oil filter. I currently have the top end apart. The piston and cylinder both look great, measures in spec and have no signs of scoring or any excessive wear. Didn't notice any metal shavings on the crank when looking at it with the cylinder removed. The metal appears to be aluminium, as it won't pick up with a magnet. What could be the source of aluminum bits in the engine? What do I need to look for? I am doing the top end because the bike was getting hard to start and showed all the signs of worn valves. Didn't notice any odd noises when it was running and this is the first time I noticed any metal debris in the engine. Thanks in advance.

[XC-Kx250]

What did your piston and cylinder look like? Any pics?

[ajw9173]

Sorry, no pics at this time. However, I saw nothing that would lead me to suspect the piston or cylinder. What else could be shedding aluminum?

[JJRace]

cam tower is aluminum

check the valve cover as it is magnesium for damage

cam chain tensioner has aluminum

oil pump - requires splitting the case

stator and flywheel rubbing?

[vlad7890]

With no damage in the piston/cylinder/head area I would put my bet on the transmission oil migrating to the engine oil area. Those particles you're seeing are likely from the clutch basket. You might want to search the forum for the existing posts on this issue.

[dstollys]

cam tower is aluminum

check the valve cover as it is magnesium for damage

cam chain tensioner has aluminum

oil pump - requires splitting the case

stator and flywheel rubbing?

what he said. 1st thing i thought of was oil pump.

[ajw9173]

Thanks for your replies everyone. Can you seperate the cases without a case splitter? The manual didn't mention using one.