I just rebuilt my entire engine. Top and bottom end. All new bearings and seals in the bottom. New wiseco top. Before i rebuilt it, it seized up. Something in the bottom end was stuck. The oil filter was covered in metal. So i tore it down and replaced all but the left side primary drive shaft bearing and the shift drum bearing on the left as well. finished it and it ran great. i still saw a few flakes in the oil but i thought this was typical of an engine after catastrophic failure and rebuild such as this. i rode very easy and broke the motor in completely. after about 3 rides (changing the oil every time) the flakes started to appear more and more. the bike started to lose power which was VERY noticeable. still seems to run fine and i checked everything else. even did a leakdown and came out fine. my question is could it be a bad bearing in the bottom. maybe something w/ the crank ( ie. bent, bad rod bearing etc..) that would cause it to lose power and metal flakes to appear. how can you tell that a bearing is bad. they all turned freely and smooth and the rod had no play in it??? any input??